Question

Omar is participating in a -day cross-country biking challenge. He biked for 67,60 ,69 ,68 , and 70 miles on the first five days. How many miles does he need to bike on the last day so that his average (mean) is 67 miles per day?

Answer 1

68 miles

Explanation:

Distance biked on the first five days =67,60 ,69 ,68 , and 70 miles

Let the distance biked on the sixth day=x miles

We want his average for the 6 days =67 miles per day

Therefore:

`Average=(67+60+69+68+70+x)/(6) \\67=(334+x)/(6)\\$Cross multiply\\67*6=334+x\\402=334+x\\x=402-334\\x=68 miles`

He needs to bike 68 miles on the sixth day to get an average of 67 miles per day/