Question

Blair's average on the first five in-class tests is 67. If this is not pulled up to at least a 70,
Blair will not be allowed to watch any more of their favorite Netflix shows. To avoid
losing those access privileges, what is the lowest score Blair can afford to earn on the last
in-class test? Assume that all tests carry equal weight.

Answer 1

Answer:

85

Step-by-step explanation:

x/5 = 67

x=335

(x+y)/6 = 70

(335+y)/6 = 70

335+y=420

y=85

Answer 2

Answer:

85

Step-by-step explanation:

Average is calculated as

average = $\frac{sum}{count}$

Here

$\frac{sum}{5}$ = 67 ( multiply both sides by 5 )

sum = 335

let x be the mark required to raise average to 70 , then

$\frac{335+x}{6}$ = 70 ( multiply both sides by 6 )

335 + x = 420 ( subtract 335 from both sides )

x = 85

Blair must score at least 85 on his last test