Round the given number to the nearest 1 000 000 000.
D
Practice makes perfect
We want to match the given number with its closest approximation written as the product of a single digit and a power of 10.
Given Number
7 257 993 201 [0.8em]
Approximations
A. 8* 10^8 B. 6* 10^(- 4) C. 7* 10^(- 4) D. 7* 10^9Let's start by rounding the given number to the nearest 1 000 000 000. Since the digit in the hundred millions place is less than or equal to 5, we will not modify the digit in the billions place.
7 257 993 201 ≈ 7 000 000 000
Finally, we will rewrite the approximations.
Choice
Approximation
Number
A.
8* 10^8
800 000 000
B.
6* 10^(- 4)
0.0006
C.
7* 10^(- 4)
0.0007
D.
7* 10^9
7 000 000 000
We can see that the closest approximation is choice D.
Alternative Solution
Rewriting the number
We are given a number and want to match it to its closest approximation.
7 257 993 201
Let's use the approximation we found in the main solution and rewrite it.
7 257 993 201 ≈ 7 000 000 000
We will write it as the product of a single digit and a power of 10. Let's start by factoring out 7!
