+76 I have a bag of marbles, where each marble is pink or yellow. The ratio of pink marbles to yellow marbles is 3:5. If there are total of 72 marbles in the bag, how many are pink?
+4622 We have 3x+5x=72, 8x=72, x=9 marbles. Since pink is 3x, we have 3*9=27 marbles.
+9481 Let the number of pink marbles = p
Let the number of yellow marbles = y
The ratio of pink marbles to yellow marbles is 3:5 . This means...
the number of pink marbles / the number of yellow marbles = 3 / 5
p / y = 3 / 5
There are a total of 72 marbles in the bag. So...
the number of pink marbles + the number of yellow marbles = 72
p + y = 72
y = 72 - p
Now we can use this value of y in the first equation and solve for p .
p / (72 - p) = 3 / 5
Multiply both sides of the equation by 5 .
5p / (72 - p) = 3
Multiply both sides by (72 - p)
5p = 3(72 - p)
5p = 216 - 3p
Add 3p to both sides.
8p = 216
Divide both sides by 8 .
p = 27
the number of pink marbles = 27
