Answer:
-4c + 5d
Step-by-step explanation:
3 - 7 = -4, so c is equal to -4.
Since there is only one value for d, d stays the same as 5d.
Answer:
$10
Step-by-step explanation:
x is her weekly allowance.
She spent half her allowance and has ½x remaining.
She earned $7, and now has $12.
12 = ½x+7
x = 10
Answer:
3x/4 = 5
Step-by-step explanation:
3 pipes take 12 hours
⇒ In 1 hour, the 3 pipes can fill 1/12 of the pool
2 of the pipes take 18 hours
⇒ in 1 hour, the 2 pipes can fill 1/18 of the pool
In 1 hour, the third pipe alone can fill :

Time needed :

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Answer: It will take 36 hours for the third pipe to fill the pool.----------------------------------------------------------------------------------------