Yes correct x is 48.02 here is why.
simplify 45.6/109.2 to 0.417582
multiply both sides by 115
simplify 0.417582 x 115 to 48.021978
switch sides
Answer: x = 48.021978
This is the answer for the first one
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.----------------------------------------------------------------------------------------
2(5x + 15) + 2<span>(4x + 3) = 360
10x + 30 + 8x + 6 = 360
18x = 324
x = 18
so
RST = </span><span>5x + 15 = 5(18) + 15 = 105
answer
RST = 105 degree</span>