the ratio of red marbles to blue marbles in a jar is 5:3.If there are 40 marbles,how many blue marbles marbles are there?
MathBot Answer:
Given:\[\begin{aligned}\text{num red marbles} : \text{num blue marbles} = 5 : 3\end{aligned}\]It follows:\[\begin{aligned}\frac{\text{num red marbles}}{\text{num blue marbles}} = \frac{5}{3}\end{aligned}\]If there are 40 marbles, then:\[\begin{aligned}\text{num red marbles} + \text{num blue marbles} = 40\end{aligned}\]Therefore:\[\begin{aligned}\text{num blue marbles} = \frac{3}{5} \times \left(40 - \text{num blue marbles}\right) = 15\end{aligned}\]