The problem asks us to fill in the missing numbers in three equations and identify which numbers round to 80 when rounded to the nearest 10.

1. Problem Description

The problem asks us to fill in the missing numbers in three equations and identify which numbers round to 80 when rounded to the nearest

1

0.

2. Solution Steps

First Equation:

We have $\Box + 85 = 200$. To find the missing number, we subtract 85 from

2

0

0. $200 - 85 = 115$.

So the missing number is

1

1

5.

Second Equation:

We have $4 \times \Box = 120$. To find the missing number, we divide 120 by

4. $120 \div 4 = 30$.

So the missing number is

3

0.

Third Equation:

We have $120 - 51 = \Box$. To find the missing number, we subtract 51 from

1

2

0. $120 - 51 = 69$.

So the missing number is

6

9.

Rounding to the nearest 10:

We need to determine which of the following numbers, 84, 87, 72, 76, and 90, round to

8

0. - 84: Since the ones digit is 4, which is less than 5, we round down to

8

0. - 87: Since the ones digit is 7, which is greater than or equal to 5, we round up to

9

0. - 72: Since the ones digit is 2, which is less than 5, we round down to

7

0. - 76: Since the ones digit is 6, which is greater than or equal to 5, we round up to

8

0. - 90: 90 is already a multiple of 10, so it stays

9

0.

Therefore, 84 and 76 round to

8

0.

3. Final Answer

The missing numbers are: 115, 30,

6

9. The numbers that round to 80 are: 84, 76.