Question

Christine is participating in a 4-day cross-country biking challenge. She biked for 66 ,62 ,47 and miles on the first three days. How many miles does she need to bike on the last day so that her average (mean) is 60 miles per day

Answer 1

Answer:

65 miles

Step-by-step explanation:

the average is found by adding all the variables then dividing by the amount of variables so

66 + 62 + 47 + x divided by 4 = 60  

x= 65

Answer 2

We want to see how much should Christine bike on the last day such that her average is 60 miles. We will find that she must bike 65 miles on the last day.

What is the average?

If we have a set of N numbers {x₁, x₂, ..., xₙ} the average is given by:

$A = \frac{x_1 + ... + x_n}{N}$

In this case, we have 4 values:

{66mi, 62mi, 47mi, x}

Where x represents the distance that she bikes on the last day. Now we want to solve:

$60 mi = \frac{66mi + 62mi + 47mi + x}{4} \\ \\ 4*60mi = 66mi + 62mi + 47mi + x\\ 240 mi = 175mi + x\\ \\ 240mi - 175mi = x = 65mi$

So she must bike 65 miles on her last day.

If you want to learn more about averages, you can read:

https://brainly.com/question/8728504