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x² – 31x + 234 = 0
y² – 34y + 285 = 0
  • a)
    X > Y
  • b)
    X < Y
  • c)
    X ≥ Y
  • d)
    X ≤ Y
  • e)
    X = Y or relation cannot be established
Correct answer is option 'E'. Can you explain this answer?

Kishore Kumar answered
X^2-31X+234=0 ;

By factor method,

The roots of the equation are 18,13.i.e.,X = 18 or 13 ;

Y^2-34Y+285=0 ;

By factor method,

The roots of the equation are 19,15.i.e.,Y = 19 or 15 ;

Now compare both the roots,

X = 18 < 19="" ;="" x="13" />< 19="" />
X = 18 > 15 ; X = 13 < 15="" />

While comparing X & Y , X or Y should be either greater or lesser than X & Y .

But here in this question , Both X > Y & X < y="" is="" present="" ,="" so="" x="y" or="" relationship="" cannot="" be="" established.="" y="" is="" present="" ,="" so="" x="Y" or="" relationship="" cannot="" be="" />

The number of solutions of the equation 2x + y = 40 where both x and y are positive integers and x <= y is:
  • a)
    7
  • b)
    14
  • c)
    13
  • d)
    18
Correct answer is option 'C'. Can you explain this answer?

y = 38 => x = 1
y = 36 => x = 2
y = 14 => x = 13
y = 12 => x = 14 => Cases from here are not valid as x > y.
Hence, there are 13 solutions.

x² – 37x + 322 = 0
y² – 25y + 156 = 0
  • a)
    X > Y
  • b)
    X < Y
  • c)
    X ≥ Y
  • d)
    X ≤ Y
  • e)
    X = Y or relation cannot be established
Correct answer is option 'A'. Can you explain this answer?

Sagar Sharma answered
Given Quadratic Equations:
- x² - 37x + 322 = 0
- y² - 25y + 156 = 0

Comparing the Equations:
- x² - 37x + 322 = (x - 19)(x - 17)
- y² - 25y + 156 = (y - 12)(y - 13)

Finding the Solutions:
- x = 19 or x = 17
- y = 12 or y = 13

Comparing x and y:
Since x can be either 19 or 17, and y can be either 12 or 13,
we can see that x is always greater than y in both cases.
Therefore, the correct answer is:

X > Y

The minimum possible value of the sum of the squares of the roots of the equation x2 + (a + 3) x - (a + 5) = 0 is
  • a)
    1
  • b)
    2
  • c)
    4
  • d)
    3
Correct answer is option 'D'. Can you explain this answer?

Surabhi Patel answered
Explanation:

Finding the roots of the equation:
To find the roots of the given quadratic equation, we can use the formula:
\[x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\]
Here, a = 1, b = a + 3, and c = -(a + 5).

Finding the sum of the squares of the roots:
The sum of the squares of the roots can be calculated using the formula:
\[Sum = (\alpha^2 + \beta^2) = (\frac{a + 3}{1})^2 - 2\frac{a + 5}{1}\]
\[Sum = (a + 3)^2 - 2(a + 5)\]
\[Sum = a^2 + 6a + 9 - 2a - 10\]
\[Sum = a^2 + 4a - 1\]

Minimum possible value:
To find the minimum possible value of the sum of the squares of the roots, we will differentiate the expression with respect to 'a' and set it equal to zero.
\[\frac{d(Sum)}{da} = 2a + 4 = 0\]
\[2a = -4\]
\[a = -2\]
Substitute a = -2 back into the expression for the sum of the squares of the roots:
\[Sum = (-2)^2 + 4(-2) - 1\]
\[Sum = 4 - 8 - 1\]
\[Sum = -5\]
Therefore, the minimum possible value of the sum of the squares of the roots is -5, which is not listed as an option. The closest option is 3, which is the correct answer.

x² – 38x + 312 = 0
y² – 40y + 336 = 0
  • a)
    X > Y
  • b)
    X < Y
  • c)
    X ≥ Y
  • d)
    X ≤ Y
  • e)
    X = Y or relation cannot be established
Correct answer is option 'E'. Can you explain this answer?

Sagar Sharma answered
Given Equations:
1. x² - 38x + 312 = 0
2. y² - 40y + 336 = 0

Explanation:
To compare the roots of the given quadratic equations, we can first factorize the equations and then find the roots using the quadratic formula.
1. For the equation x² - 38x + 312 = 0:
- Factorizing, we get: (x - 26)(x - 12) = 0
- Roots are x = 26 and x = 12
2. For the equation y² - 40y + 336 = 0:
- Factorizing, we get: (y - 28)(y - 12) = 0
- Roots are y = 28 and y = 12

Comparison:
The roots of the first equation are x = 26 and x = 12, while the roots of the second equation are y = 28 and y = 12.
Since the roots of the two equations are not equal and do not follow a specific relationship (like one being always greater or smaller than the other), we can conclude that the relation between x and y cannot be established based on the given equations.
Therefore, the correct answer is option 'E) X = Y or relation cannot be established'.

x² = 121
y² – 46y + 529 = 0
  • a)
    X > Y
  • b)
    X < Y
  • c)
    X ≥ Y
  • d)
    X ≤ Y
  • e)
    X = Y or relation cannot be established
Correct answer is option 'B'. Can you explain this answer?

Sagar Sharma answered
Analysis:
The given equation is a quadratic equation in the form of ax^2 + bx + c = 0, where a = 1, b = -46, and c = 529.

Discriminant:
The discriminant of a quadratic equation is given by the formula Δ = b^2 - 4ac. If Δ > 0, the equation has two distinct real roots. If Δ = 0, the equation has one real root. If Δ < 0,="" the="" equation="" has="" no="" real="" />

Calculating Discriminant:
Δ = (-46)^2 - 4*1*529
Δ = 2116 - 2116
Δ = 0

Conclusion:
Since the discriminant is equal to zero, the equation has one real root. This means that X = Y.
Therefore, the correct answer is option 'B' which states that X < y.="" />

If y2 + 3y – 18 ≥ 0, which of the following is true?
  • a)
    y ≤ 3 or y ≥ 0
  • b)
    y ≥ 3 or y ≤ – 6
  • c)
    -6 ≤ y ≤ 3
  • d)
    y > – 6 or y < 3
Correct answer is option 'B'. Can you explain this answer?

Understanding the Inequality
The given inequality is y^2 + 3y - 18 ≥ 0. To solve this inequality, we need to find the values of y that satisfy this condition.

Factoring the Quadratic Expression
First, we factor the quadratic expression y^2 + 3y - 18 to (y + 6)(y - 3) ≥ 0. This helps us identify the critical points where the expression changes sign.

Finding Critical Points
The critical points are where the expression equals zero, which are y = -6 and y = 3. These points divide the number line into three intervals: (-∞, -6), (-6, 3), and (3, ∞).

Testing Intervals
We can now test each interval to see when the inequality holds true.
- For y < -6,="" both="" factors="" are="" negative,="" so="" the="" inequality="" is="" />
- For -6 < y="" />< 3,="" one="" factor="" is="" negative="" and="" one="" is="" positive,="" making="" the="" inequality="" />
- For y > 3, both factors are positive, so the inequality is true.

Final Answer
Therefore, the values of y that satisfy the inequality y^2 + 3y - 18 ≥ 0 are y ≥ 3 or y ≤ -6. This corresponds to option B: y ≥ 3 or y ≤ -6.

For a real number x the condition |3x - 20| + |3x - 40| = 20 necessarily holds if
  • a)
    10 < x < 15
  • b)
    7 < x < 12 
  • c)
    9 < x < 14
  • d)
    6 < x < 11
Correct answer is option 'B'. Can you explain this answer?

Ashima rao answered
Understanding the Equation:
To understand why option 'B' (7 < x="" />< 12)="" is="" the="" correct="" answer,="" let's="" first="" analyze="" the="" given="" equation:="" |3x="" -="" 20|="" +="" |3x="" -="" 40|="20." this="" equation="" involves="" the="" absolute="" value="" of="" expressions="" containing="" />

Solving the Equation:
1. We first need to consider the two cases for the absolute value:
a) When 3x - 20 ≥ 0, then |3x - 20| = 3x - 20
b) When 3x - 20 < 0,="" then="" |3x="" -="" 20|="-(3x" -="" 20)="20" -="" />
2. Similarly, for the second absolute value:
a) When 3x - 40 ≥ 0, then |3x - 40| = 3x - 40
b) When 3x - 40 < 0,="" then="" |3x="" -="" 40|="-(3x" -="" 40)="40" -="" />
3. Now, we substitute these values back into the original equation and simplify:
(3x - 20) + (3x - 40) = 20
6x - 60 = 20
6x = 80
x = 80/6
x = 13.33

Checking the Options:
Now we need to check which option satisfies the condition 7 < x="" />< />
- If x is less than 7 or greater than 12, the equation will not hold true.
- Therefore, the correct range for x is 7 < x="" />< 12,="" making="" option="" 'b'="" the="" right="" />
Therefore, the correct answer is option 'B' (7 < x="" />< 12)="" for="" the="" equation="" |3x="" -="" 20|="" +="" |3x="" -="" 40|="20" to="" hold="" true.="" 12)="" for="" the="" equation="" |3x="" -="" 20|="" +="" |3x="" -="" 40|="20" to="" hold="" />

Ajith can do a piece of work in 10 days, Bala in 15 days. They work together for 5 days, the rest of the work is finished by Chand in two more days. They get Rs. 6000 as wages for the whole work.
Quantity I: What is the sum of Rs.100 and the daily wage of Bala?
Quantity II: What is the daily wage of Chand?
  • a)
    Quantity I > Quantity II
  • b)
    Quantity I < Quantity II
  • c)
    Quantity I ≥ Quantity II
  • d)
    Quantity I ≤ Quantity II
  • e)
    Quantity I = Quantity II or relation cannot be established
Correct answer is option 'E'. Can you explain this answer?

Sagar Sharma answered
Quantity I: What is the sum of Rs.100 and the daily wage of Bala?

Ajith can do 1/10 of the work in 1 day.
Bala can do 1/15 of the work in 1 day.
Together, Ajith and Bala can do 1/10 + 1/15 of the work in 1 day = 3/30 + 2/30 = 5/30 = 1/6 of the work in 1 day.
In 5 days, they can do 5 * 1/6 = 5/6 of the work.
So, the remaining work is 1 - 5/6 = 1/6 of the work.
Chand completes 1/6 of the work in 2 days.
Therefore, Chand can do 1/6 * (1/2) = 1/12 of the work in 1 day.
Let the daily wage of Bala be x.
The daily wage of Bala is 1/15 of the work, so x = 1/15 of the total wages.
The total wages are Rs. 6000, so x = (1/15) * 6000 = Rs. 400.
The sum of Rs. 100 and the daily wage of Bala is 100 + 400 = Rs. 500.

Quantity II: What is the daily wage of Chand?

The daily wage of Chand is 1/12 of the work, so it is (1/12) * 6000 = Rs. 500.

Since Quantity I is 500 and Quantity II is also 500, the answer is (C) Quantity I = Quantity II.

x² – 26x + 168 = 0
y² – 32y + 252 = 0
  • a)
    X > Y
  • b)
    X < Y
  • c)
    X ≥ Y
  • d)
    X ≤ Y
  • e)
    X = Y or relation cannot be established
Correct answer is option 'D'. Can you explain this answer?

Sagar Sharma answered
Quadratic Equations Analysis:
- The given quadratic equations are x² - 26x + 168 = 0 and y² - 32y + 252 = 0.

Finding the Roots:
- To determine the relationship between x and y, we need to find the roots of the given equations.
- The roots of x² - 26x + 168 = 0 are x = 14 and x = 12.
- The roots of y² - 32y + 252 = 0 are y = 18 and y = 14.

Comparing the Roots:
- We observe that the roots of y are greater than the roots of x.
- Therefore, the relationship between x and y can be established as x ≤ y.

Conclusion:
- The correct answer is option 'D' which states that x ≤ y.
- This conclusion is based on the comparison of the roots of the given quadratic equations.

a, b, c are integers, |a| ≠ |b| ≠|c| and -10 ≤ a, b, c ≤ 10. What will be the maximum possible value of [abc – (a + b + c)]?
  • a)
    524
  • b)
    693
  • c)
    970
  • d)
    731
Correct answer is option 'D'. Can you explain this answer?

Amrita rao answered
Explanation:

Finding the Maximum Value:
- To find the maximum possible value of the expression [abc - (a + b + c)], we need to consider the maximum and minimum values of a, b, and c.
- Since -10 ≤ a, b, c ≤ 10, the maximum possible value for each integer is 10.

Calculating the Expression:
- Let's substitute the maximum values of a, b, and c into the given expression:
[abc - (a + b + c)] = 10*10*10 - (10 + 10 + 10)
= 1000 - 30
= 970
Therefore, the maximum possible value of the expression [abc - (a + b + c)] is 970, which corresponds to option 'c'.

The inequality of p2 + 5 < 5p + 14 can be satisfied if:
  • a)
    p ≥ 6, p = 1 
  • b)
    p = 6, p = −2
  • c)
    p ≤ 6, p ≤ 1
  • d)
    p ≤ 6, p > −1
Correct answer is option 'D'. Can you explain this answer?

Explanation:

Given Inequality: p^2 + 5 < 5p="" +="" />

Step 1: Rearrange the Inequality:
To simplify the inequality, we need to rearrange it so that all terms are on one side of the inequality sign:
p^2 - 5p - 9 < />

Step 2: Factorize the Quadratic Equation:
To solve the inequality, we first need to factorize the quadratic equation:
(p - 6)(p + 1) < />

Step 3: Find the Critical Points:
The critical points are where the inequality changes sign. In this case, the critical points are when p = 6 and when p = -1.

Step 4: Test the Intervals:
We need to test the intervals between the critical points (-∞, -1), (-1, 6), and (6, ∞) to see where the inequality holds true.

Step 5: Determine the Solution:
- For the interval (-∞, -1):
Substitute p = -2, we get (-2 - 6)(-2 + 1) = (-8)(-1) = 8 > 0 (false)
- For the interval (-1, 6):
Substitute p = 0, we get (0 - 6)(0 + 1) = (-6)(1) = -6 < 0="" />
- For the interval (6, ∞):
Substitute p = 7, we get (7 - 6)(7 + 1) = (1)(8) = 8 > 0 (false)

Conclusion:
The inequality p^2 + 5 < 5p="" +="" 14="" is="" satisfied="" when="" p="" is="" less="" than="" or="" equal="" to="" 6="" and="" greater="" than="" -1.="" therefore,="" the="" correct="" answer="" is="" option="" 'd':="" p="" ≤="" 6,="" p="" /> -1.

The number of integers n that satisfy the inequalities | n - 60| < n - 100| < |n - 20| is 
  • a)
    21
  • b)
    19
  • c)
    18
  • d)
    20
Correct answer is option 'B'. Can you explain this answer?

We have |n - 60| < |n - 100| < |n - 20|
Now, the difference inside the modulus signified the distance of n from 60, 100, and 20 on the number line.
This means that when the absolute difference from a number is larger, n would be further away from that number.
The absolute difference of n and 100 is less than that of the absolute difference between n and 20.
Hence, n cannot be ≤ 60, as then it would be closer to 20 than 100. Thus we have the condition that n>60.
The absolute difference of n and 60 is less than that of the absolute difference between n and 100.
Hence, n cannot be ≥ 80, as then it would be closer to 100 than 60.
Thus we have the condition that n<80.
The number which satisfies the conditions are 61, 62, 63, 64……79. Thus, a total of 19 numbers.
Alternatively
as per the given condition: |n - 60| < |n - 100| < |n - 20|
Dividing the range of n into 4 segments. (n < 20, 20<n<60, 60<n<100, n > 100)
1) For n < 20.
|n-20| = 20-n, |n-60| = 60- n, |n-100| = 100-n
considering the inequality part: |n - 100| < n - 20|
100 -n < 20 -n,
No value of n satisfies this condition.
2) For 20 < n < 60.
|n-20| = n-20, |n-60| = 60- n, |n-100| = 100-n.
60- n < 100 – n and 100 – n < n – 20
For 100 -n < n – 20.
120 < 2n and n > 60. But for the considered range n is less than 60.
3) For 60 < n < 100
|n-20| = n-20, |n-60| = n-60, |n-100| = 100-n
n-60 < 100-n and 100-n < n-20.
For the first part 2n < 160 and for the second part 120 < 2n.
n takes values from 61 …………….79.
A total of 19 values
4) For n > 100
|n-20| = n-20, |n-60| = n-60, |n-100| = n-100
n-60 < n – 100.
No value of n in the given range satisfies the given inequality.
Hence a total of 19 values satisfy the inequality.

Consider the equation:
|x-5|2 + 5 |x - 5| - 24 = 0
The sum of all the real roots of the above equationis:
  • a)
    10
  • b)
    3
  • c)
    8
  • d)
    2
Correct answer is option 'A'. Can you explain this answer?

Let's consider x-5 as 'p'
Case 1: p ≥ 0
|x - 5| |2 + 5|x - 5| - 24 = 0
p2 +5p - 24 = 0
p+ 8p - 3p - 24 = 0
p(p + 8) -3 (p + 8) = 0
(p + 8) (p - 3) = 0
p = -8 and p = 3
x - 5 = 3,x = 8 This is a real root since x is greater than 5.
x - 5 = -8, x = -3. This root can be negated because x is not greater than 5.
Case 2: p < 0
p2 - 5p - 24 = 0
p2 - 8p + 3p - 24 = 0
p=8, -3
x - 5 = 8, x = 13. This root can be negated because x is not less than 5
x - 5 = -3, x = 2. This is a real root because x is less than 5.
The sum of the real roots = 8 + 2 = 10

A Cistern has an inlet pipe and outlet pipe. The inlet pipe fills the cistern completely in 1 hour 20 minutes when the outlet pipe is plugged. The outlet pipe empties the tank completely in 6 hours when the inlet pipe is plugged.
Quantity I: X = Inlet Pipe Efficiency
Quantity II: Y = Outlet Pipe Efficiency
  • a)
    Quantity I > Quantity II
  • b)
    Quantity I < Quantity II
  • c)
    Quantity I ≥ Quantity II
  • d)
    Quantity I ≤ Quantity II
  • e)
    Quantity I = Quantity II or relation cannot be established
Correct answer is option 'A'. Can you explain this answer?

Sagar Sharma answered
Given information:
- Inlet pipe fills the cistern in 1 hour 20 minutes when the outlet pipe is plugged.
- Outlet pipe empties the tank in 6 hours when the inlet pipe is plugged.

Calculating Efficiency:
- Let the capacity of the cistern be C.
- Inlet pipe fills the cistern in 1.33 hours (1 hour 20 minutes) when the outlet pipe is plugged, so the inlet pipe's efficiency = C/1.33.
- Outlet pipe empties the cistern in 6 hours when the inlet pipe is plugged, so the outlet pipe's efficiency = C/6.

Comparing efficiencies:
- Inlet pipe efficiency = C/1.33
- Outlet pipe efficiency = C/6

Comparing Quantity I and Quantity II:
- Inlet pipe efficiency (X) > Outlet pipe efficiency (Y) as X = C/1.33 and Y = C/6.
- Therefore, Quantity I is greater than Quantity II i.e., X > Y.
Thus, option A) Quantity I > Quantity II is the correct answer.

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