Answer:
363
Step-by-step explanation:
9 * 20 = 180
24 has 4 more than that, so multiply 9 to 4 and add it to 180.
9 * 4 = 36
180 + 36 = 216
So 9 * 24 = 216
My teacher taught me a simple equation for these types of problems:
(percent of solution × amount of solution) + (percent of solution × amount of solution) = (percent of solution × total amount of solution)
in simple terms: %amount + %amount = %total amount
We know don't know how much gallons of 60% solution we need so it will be represented as x. We dont know the total amount either so it would have to be both solutions added together so 50 + x. Now lets solve:
(0.60)(x) + (0.24)(50) = (0.50)(50 + x) simplify/ distribute
0.6x + 12 = 25 +0.5x get all xs on one side and numbers on other
0.1x + 12 = 25
0.1x = 13 divide both sides by 0.1 to find x
x = 130
You need 130 gallons of 60% solution.
Answer:
x = 2
y = 3
Step-by-step explanation:
y = 2x – 1
y - 2x = -1
y = 5x – 7
y - 5x = -7
y - 2x = -1
y - 5x = -7
_________--
3x = 6
x = 6/3
x = 2
y = 2x – 1
y = 2(2) - 1
y = 4 - 1
y = 3