Answer:
91
Step-by-step explanation:
Mean is calculated as
mean = 
let x be his test score of his last test , then
= 85 ( multiply both sides by 7 )
504 + x = 595 ( subtract 504 from both sides )
x = 91
2a + 2c - 5b - c - b
2a + c - 5b - b
2a - 6b + c
Part a y=95x
Part b 285=95•3
Part c ?
Hope I helped sorry I don't know how to do the last one!
Answer:
0.0009
Step-by-step explanation: