Question

\(100-52.72=\) Write your answer in the blank.

Short answer

47.28

Step-by-step solution

Set Up the Equation

Align the numbers by their decimal points so it’s easier to subtract. Subtract starting from the rightmost digit (the hundredths place).

Perform Subtraction

Start subtracting from the rightmost digit: 0 - 2 = -2 (since we can't subtract 2 from 0, borrow from the next digit to the left). Borrowing: Now, 10 - 2 = 8. So, we place 8 in the hundredths place. Continuing with the tenths place: 9 - 7 = 2. Place 2 in the tenths place. Move to the ones place: Borrowing again (if necessary): 9 - 2 = 7. Place 7 in the ones place. Finally, in tens place: 0 (left, after borrowing) - 5 = -5. 10 (borrowed again transform this prior] to 10 - 5 = 4. Therefore, place 4 to tens.

Write Down the Final Answer

Put all the digits and decimal point together to get the final answer: 100 - 52.72 = (47.28).

Key concepts

Decimal Subtraction

Decimal subtraction involves subtracting numbers that have digits to the right of the decimal point. To subtract decimals, it's important to align the numbers by their decimal points. This makes sure that digits of the same place value are being subtracted. In our exercise, we want to subtract 52.72 from 100.
We write it like this:
\( 100.00 - 52.72 \)
When set up this way, it's clear where we may need to borrow digits.

Borrowing in Subtraction

Borrowing in subtraction is needed when a digit in the minuend (top number) is smaller than the digit below it in the subtrahend (bottom number). For the problem 100 - 52.72:

• Start in the hundredths place: we have 0 and want to subtract 2. Since 0 < 2, we need to borrow. Borrow from the tenths place, turning the 0 into 10, so now we do 10 - 2 = 8.
• Next, in the tenths place, is now 9 (since we borrowed 1). Do 9 - 7 = 2.
• In the ones place: borrow from the tens. Turn the 0 into 10, do 10 - 2 = 8, but after borrowing, we get 7.
• Finally, the tens place: we borrowed one to get 9, then borrowed again, leaving 8. Do 10 - 5 = 5.

After borrowing, put everything together to find the final answer.

Step-by-Step Math Solutions

Following a step-by-step approach ensures clarity and minimizes errors. Let’s break down the solution for 100 - 52.72:
1. **Align the numbers** by decimal points.
\[ 100.00 - 52.72 \]
2. **Subtract from the rightmost digit**:

• Tenths: 10 (borrowed) - 2 = 8.
• Hundredths: 9 (borrowed) - 7 = 2.
• Ones: 10 (borrowed) - 2 = 8 (actual 7 due to earlier borrow).
• Tens: 10 (borrowed) - 5 = 4.

3. **Combine all the digits**:
\( 47.28 \)
This method helps you see where each number goes and how borrowing affects the digits.