Question

in a bookshelf, the numberof books on socialStudies to the number of books on Economics is 7:11, whereas the number of books on Economics to the number of books on Mathematics is 22:19. What is the ratio of the number of books on SocialStudies to the Mathematics books?​

Answer 1

The ratio of number of books of Social Studies to the number of books of Mathematics is 14:19.

• Let the number of books of economics be $N_E$ , number of books of Mathematics be  $N_M$ and the number of books of Social studies be $N_S$.

• The ratio of number of books of social studies to the number of books of economics is 7:11.

$\frac{N_S}{N_E}$ = $\frac{7}{11}$

• The ratio of number of books of economics to the number of books of mathematics is 22:19.

$\frac{N_E}{N_M}$ = $\frac{22}{19}$

• Now, we have to find the ratio of number of books of social studies to the number of books of mathematics .

$\frac{N_S}{N_M}$ = $\frac{N_S}{N_E}$ × $\frac{N_E}{N_M}$

$\frac{N_S}{N_M}$ = $\frac{7}{11}$ × $\frac{22}{19}$

$\frac{N_S}{N_M}$ =  $\frac{14}{19}$

• The ratio of number of books of Social Studies to the number of books of Mathematics is 14:19.