Answer:
About 5 hr 10 min
Step-by-step explanation:
rate 1 = 1 pool / 9 hrs rate 2 = 1 pool / 12 hours
now find the time with both rates combined
1 pool / ( 1/9 + 1/12) = 1/ (7/36) = 36/7 hr = 5 1/7 hr = 5 hr 8.6 min
Answer:
Jason still has 39 stickers.
Step-by-step explanation:
First, 57 + 64 + 71 = 192
Second, 231 - 192 = 39
Hope this helps!
Answer:
18 gallons containing 20% solvent and 6 gallons containing 60% solvent
Step-by-step explanation:
the painter needs 24 gallons of paint containing 30% solvent = 7.2 gallons of solvent
let a = 20% solvent paint
let b = 60% solvent paint
a + b = 24
0.2a + 0.6b = 7.2
(replace a = 24 - b in the second equation)
a + b = 24
0.2(24 - b) + 0.6b = 7.2
4.8 - 0.2b + 0.6b = 7.2
0.4b = 7.2 - 4.8 = 2.4
b = 2.4 / 0.4 = 6
a = 24 - 6 = 18
You need to make $300 for a new computer. You have $60 already and you can earn $8 for every lawn that you mow. How many lawns do you need to mow to earn at least $300?
3 / 5 = (x+1) / (y-2)
↓
↓ multiply by 5 / 3
↓
1 = 5 * (x+1) / 3 * (y-2)
↓
↓ move and simplify
↓
5x + 5 = 3y - 6
↓
↓ minus 5
↓
5x = 3y - 11
↓
↓ divide by 5
↓
Answer : x = (3y - 11) / 5