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

21 red marbles

Step-by-step explanation:

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

The proportion of red marbles in the bag

`\begin{gathered} =(3)/(3+4) \\ =(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} \\ =(3)/(7)*49 \\ =3*7 \\ =21 \end{gathered}`

There are 21 red marbles in the bag.