Audreys free-throw percentage so far this season is. 875. If she makes only 13 of her next 20 free throws, her percentage will drop to. 860. How many free throws has Audrey made this season?

solve using a guess and check method

Answer: 245

Explanation:

From the question, Audreys free-throw percentage this season is 0.875 and if she makes only 13 of her next 20 free throws, the percentage will drop to 0.860. To calculate the number of free throws Audrey has made this season goes thus:

Audrey's current rate = 0.875

Let us say y out of z should be 0.875

y/z = 0.875 ... equation i

Therefore,

y+13/z+20 = 0.860 ... equation ii

Recall that y/z = 0.875

y = 0.875z

Put the value of y into equation ii

y+13/z+20 = 0.860

0.875z + 13/z + 20 = 0.860

Cross multiply

0.875z + 13 = 0.860 (z + 20)

0.875z + 13 = 0.860z + 17.2

Collect like terms

0.875z - 0.860z = 17.2 - 13

0.015z = 4.2

z = 4.2/0.015

z = 280

Since y = 0.875z

y = 0.875 * 280

y = 245

Therefore, the number of throws Audrey made this season is 245