The respective ratio between the present age of Mary and Deepa is x :4...
Prema’s age after 8 years = 33 years
Prema’s present age = 33 – 8= 25 years
Mary’s present age = 25 – 8 = 17 years
Deepa’s present age = 17 + 25 = 42 years
Ratio between Mary and Deepa = 17 : 42
X = 17
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The respective ratio between the present age of Mary and Deepa is x :4...
The respective ratio between the present age of Mary and Deepa is x :4...
's age is 2 times the age of Deepa. If the difference between the present ages of Prema and Deepa is 20 years, then the value of x is:
Let's start by finding the age of Deepa. If Prema's age is 2 times the age of Deepa, and the difference between their present ages is 20 years, we can set up the following equation:
2D - D = 20
Simplifying this, we get:
D = 20
So, Deepa is currently 20 years old.
Now, we know that Mary's age is x/42 times Deepa's age. So, we can set up the following equation:
M = (x/42)D
We also know that Mary is 8 years younger than Prema. So, we can set up another equation:
M = P - 8
Finally, we know that Prema's age is 2 times Deepa's age. So, we can set up one more equation:
P = 2D
Now we have three equations and three variables (M, P, and D), so we can solve for x. First, we'll use the equation P = 2D to substitute for P in the other equations:
M = P - 8
M = 2D - 8
Now we can substitute (x/42)D for M:
(x/42)D = 2D - 8
Multiplying both sides by 42:
xD = 84D - 336
Simplifying:
83D = 336
D = 4
So, Deepa is currently 4 years old. Now we can use this to find the value of x:
M = (x/42)D
M = (x/42)4
M = (2/21)x
And we also know that P = 2D:
P = 8
Finally, we know that the difference between P and D is 20:
P - D = 20
8 - 4 = 20
This is not true, so we made a mistake somewhere. Let's go back and check our work.
We made an error when we substituted P = 2D into the equation M = P - 8. It should be:
M = 2D - 8
Now, let's redo the calculations:
M = (x/42)D
M = (x/42)4
M = (2/21)x
P = 2D
P = 2(4)
P = 8
P - D = 20
8 - 4 = 20
This is still not true, so we made another mistake. Looking back at our equations, we see that we made an error in the equation M = (x/42)D. It should be:
M = (x/42)(2D)
Now, let's redo the calculations:
M = (x/42)(2D)
M = (x/21)D
P = 2D
P = 2(4)
P = 8
P - D = 20
8 - 4 = 20
This is still not true, so we made yet another mistake. Looking back at our equations, we see that we made an error in the equation M = P - 8.