When it comes to finding the percent of something, you simply divide the percent by 100 and multiply that number by the given amount, like so:
105*.17=17.85
$17.85
The answer is B. You add all the numbers together and divide by the amount of numbers you have to find the mean. The missing height is 62 because 54+57+59+63+66+68+70+58=563
563/9 (amount of numbers you have including the missing height) = 63
3x-22+x=180
4x-22=180
4x=202
X=202/4
X=50.5
3(50.5)-22=129.5
5-.5+129.5=180