The number of races that were 10-kilometer long is 102.
An athlete ran a total of 1,500 kilometers in a race before retiring. The athlete completed 32 races that were at least 15 kilometers in length. The rest were 10-kilometer races. We need to find out the number of races that were 10-kilometer long.
Let the number of races that were 10-kilometers long be denoted by the variable "x". An equation is a formula in mathematics that expresses the equivalence of two expressions by linking them with the equal sign. We can write the equation as given below.
32×15 + 10x = 1,500
480 + 10x = 1,500
10x = 1,500 - 480
10x = 1,020
x = 1,020/10
x = 102
Hence, the number of races that were 10-kilometer long is 102.
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