Answer:
-1110/39 is the number
Step-by-step explanation:
We want to find the number should be added to both numerator and denominator of the ratio 29 : 36 to make it equal to 3:42
Let the number to be added be x.
Thus;
(29 + x) : (36 + x) = 3:42
The proportion symbol is essentialy a division symbol.
Thus;
(29 + x)/(36 + x) = 3/42
Cross multiply to give;
42(29 + x) = 3(36 + x)
1218 + 42x = 108 + 3x
1218 - 108 = 3x - 42x
1110 = - 39x
x = -1110/39
