Test: Decimals - Class 5 MCQ

To arrange the decimals in ascending order, compare each digit from left to right. Starting with the whole number part:

Comparison of Numbers

• The smallest numbers are 24.560 and 24.562.
• Comparing their decimal parts: 24.560 has a thousandths place of 0, while 24.562 has 2, making 24.560 smaller.
• Next, 45.1 is less than 54.02.

Thus, the correct order is 24.560 < 24.562 < 45.1 < 54.02.

• A and B are two decimal numbers.
• The integral part of a number is the whole number part, before the decimal point.

The question says that the integral part of A is greater than the integral part of B.

• For example, if A=4.5 and B=3.9, the integral part of A is 4, and the integral part of B is 3. Since 4 is greater than 3, A is definitely greater than B, even though the fractional parts (like 0.5 and 0.9) don't matter much here.

So, if the integral part of A is greater than that of B, then A is always greater than B.

• Decimals are numbers with a “dot” and digits after it.
• Like decimals have the same number of digits after the dot.

1. 0.2356 and 0.0235

   • Each has 4 digits after the dot.

   • So they are like decimals. ✔

2. 5.0236 and 0.23564

   • One has 4 digits after the dot, the other has 5 digits.

   • They are unlike decimals, not “fractions.” ✘

Answer: Julia is right—0.2356 and 0.0235 are like decimals.

Correct answer is B.
40 + 2/100 + 3/1000 + 5/10000
= 40 + 0.02 + 0.003 + 0.0005
= 40.0235

We know that when twice the value of A is subtracted from B, the result is 543.3202. Given that A is 548.355, we can set up the following equation:

B - 2A = 543.3202

Substituting the value of A:

B - 2(548.355) = 543.3202

This simplifies to:

B - 1096.710 = 543.3202

Now, add 1096.710 to both sides:

B = 543.3202 + 1096.710

B = 1640.0302

Next, we need to find 2(A + B):

First, calculate A + B:

• A + B = 548.355 + 1640.0302
• A + B = 2188.3852

Now, multiply by 2:

• 2(A + B) = 2 * 2188.3852
• 2(A + B) = 4376.7704

The final result is 4376.7704.

To find the other decimal Jack mistakenly multiplied, follow these steps:

• Start with the known product: 8.1443.
• Jack intended to multiply 35.41 by 4.5.
• Calculate the correct product: 35.41 × 4.5 = 159.345.
• Now, to find the other decimal, divide the product by 35.41:
  Other Decimal = 8.1443 / 35.41.
• The result of the division is approximately 0.2294.
• This suggests that the other decimal is closest to 0.23.

• X − Y = 1459.55 (X is 1459.55 more than Y)
• X + Y = 1545.55

Step 1: Find X

Add the two equations:
(X − Y) + (X + Y) = 1459.55 + 1545.55  
2X = 3005.10  
X = 3005.10 ÷ 2 = 1502.55  

Step 2: Find Y

Plug X back into X + Y = 1545.55:
1502.55 + Y = 1545.55  
Y = 1545.55 − 1502.55 = 43.00  

Step 3: Find Z

X is 542.31 less than Z, so
Z = X + 542.31 = 1502.55 + 542.31 = 2044.86 

Step 4: Add them all
X + Y + Z = 1502.55 + 43.00 + 2044.86 = 3590.41

To find the number that is 4.2456 less than the product of 45.21 and 9.76, follow these steps:

• First, calculate the product: 45.21 × 9.76.
• The result is 441.2566.
• Next, subtract 4.2456 from this product:
• 441.2566 - 4.2456 = 437.011.

The final result is 437.011.