Question

A bag contains red marbles and blue marbles. The ratio of red marbles to blue marbles is 3 to 4. If there are a total of 49 marbles in the bag, how many marbles are red?

Answer 1

Answer:

21 red marbles

Explanation:

The ratio of red marbles to blue marbles = 3 : 4.

The proportion of red marbles in the bag

$\begin{gathered} =\frac{3}{3+4} \\ =\frac{3}{7} \end{gathered}$

If the total number of marbles in the bag = 49

Then, the number of marbles which are red

$\begin{gathered} =\text{Proportion of red marbles x Total number of marbles} \\ =\frac{3}{7}\times49 \\ =3\times7 \\ =21 \end{gathered}$

There are 21 red marbles in the bag.