Powers of ten! is the answer
st + 3t = 6 for s
Subtract 3t to both sides
st + 3t - 3t = 6 - 3t
Simplify
st = 6 - 3t
Divide both sides by t
st/t = (6-3t)/3
simplify
s = 6/3 - 3t/3
s = 2 - t
Answer:
if there is equivalent ratio cookies should be 48
New x = old x + 9
new y + old y - 22
Increased by 15
past score was x
increased by 15 means he raised to 15+x
it was raised to 83%
therefor
x+15=83
first option is right (and first test was 68%)
