Question

The US national debt was $2.9617 x 10^13 in 2021 and $3.98 x 10^11 in 1971. Find how much the debt increased in the 50-year period.

answers:

$2.9219 x 10^11

$1.0183 x 10^24

$3.0015 x 10^13

$2.9219 x 10^13

Answer 1

are you sure

Answer 2

To find the increase in the US national debt from 1971 to 2021, we can subtract the debt in 1971 from the debt in 2021.

The debt in 2021 is \( 2.9617 \times 10^{13} \) and the debt in 1971 is \( 3.98 \times 10^{11} \).

First, let's express the debt in 1971 in the same order of magnitude as the debt in 2021 by converting it:

1. Convert \( 3.98 \times 10^{11} \) to \( 10^{13} \) form:
\[
3.98 \times 10^{11} = 0.0398 \times 10^{13}
\]

Now we subtract the two values:
\[
2.9617 \times 10^{13} - 0.0398 \times 10^{13}
\]

Performing the subtraction:
\[
(2.9617 - 0.0398) \times 10^{13} = 2.9219 \times 10^{13}
\]

Thus, the increase in the US national debt over the 50-year period from 1971 to 2021 is \( 2.9219 \times 10^{13} \).

The correct answer is:
**$2.9219 x 10^{13}**

Answer 3

Let's double-check the calculations step by step.

1. **US National Debt in 2021**:
- \(2.9617 \times 10^{13}\)

2. **US National Debt in 1971**:
- \(3.98 \times 10^{11}\)

To find the increase in national debt, we will subtract the 1971 debt from the 2021 debt.

3. **Convert the 1971 debt to \(10^{13}\)** for easier subtraction:
- \(3.98 \times 10^{11} = 0.0398 \times 10^{13}\)

4. **Subtract the two values**:
- \(2.9617 \times 10^{13} - 0.0398 \times 10^{13} = (2.9617 - 0.0398) \times 10^{13}\)
- \(2.9219 \times 10^{13}\)

So yes, the calculation is correct. The increase in the US national debt over the 50-year period from 1971 to 2021 is indeed:

**$2.9219 \times 10^{13}**

If you have any further questions or need clarification on any step, feel free to ask!