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
Answer: Tom will pay $20.01 lesser than the original price.
Step-by-step explanation:
The original price of the phone is $137.99. It is now on sale for 1/10 off the original price. This means that the discount on the original price is 1/10 × 137.99 = 13.799. The new price will be the original price - the discount.
The new price is 137.99 - 13.799 = $124.191
Tom has a coupon for an extra 5% off the sale price. It means that Tom would pay 5% off $124.191. The amount that Tom would pay will be
124.191 - (5/100 × 124.191) = 124.191 - 6.20955 = $117.98
The difference between the original price and the price that Tom will pay is
137.99 - 117.98 = $20.01
Answer:
5. 7(x - 2) + 1 = -34
7x - 14 + 1 = -34
7x - 13 = -34
7x = -34 + 13
7x = -21
x = -21/7 = -3
6. 10x + 4 - 8x = 2(x - 1)
2x + 4 = 2x - 2
Cancel 2x means this equation has no solution
8. 5(x - 3) + 1 = 5x - 14
5x - 15 + 1 = 5x - 14
5x - 14 = 5x - 14
5x - 5x = -14 + 14
0
9. 2x + 3 = 5x + 3 - 3x
2x + 3 = 2x + 3
2x - 2x = 3 - 3
0
11. x + 2x + 1 = 3x + 5
3x + 1 = 3x + 5
Cancel 3x means this equation has no solution
12. -3 = -2x + 4/-4
-3 × (-4) = -2x + 4
12 = -2x + 4
12 - 4 = -2x
8 = -2x
8/-2 = x
-4 = x
