Answer:
If two expressions are equal to each other, and you add the same value to both sides of the equation, the equation will remain equal. When you solve an equation, you find the value of the variable that makes the equation true. In order to solve the equation, you isolate the variable.
Answer:
D
Step-by-step explanation:
I believe it is 60 inches
Answer:
534,070.75 miles
Step-by-step explanation:
The circumference formula is
or
.
But since we're given the diameter, 170,000, all we have to do is multiply it by
.

The question also states that Lucy has a winning probability of 1/50, which means that she has 1 chance of winning if the total runners were 50. Therefore, there are 49 runners who may be faster than her.
The fact that Lucy is the 50th slowest runner, means that starting from the slowest she is in 50th position, therefore there are 49 runners that are slower than her.
The total number of runners will be the sum of those faster than Lucy, those slower than Lucy and Lucy:
49 + 49 + 1 = 99
There are 99 runners in Lucy's school.