Question

John ate $\frac{3}{13}$ of a chocolate cake and Alex ate another $\frac{5}{13}$. part of the chocolate cake would be left now.

• A. $\frac{8}{13}$
• B. $\frac{1}{13}$
• C. $\frac{5}{13}$

Answer 1

The correct option is C $\frac{5}{13}$

Part of chocolate cake eaten by John $=\frac{3}{13}$
Part of chocolate cake eaten by Alex $=\frac{5}{13}$

Part of chocolate cake eaten by John and Alex
$=\frac{3}{13}$+$\frac{5}{13}$

Concept: Only the numerators of both fractions are added or subtracted when two fractions with the same denominator are added or subtracted.

$\Rightarrow \frac{3}{13}$+$\frac{5}{13}=\frac{3+5}{13}=\frac{8}{13}$


Part of the cake left now = Total part of the cake - Part of cake eaten by John and Alex

$\Rightarrow 1-\frac{8}{13}=\frac{13}{13}-\frac{8}{13}=\frac{13-8}{13}=\frac{5}{13}$

$\therefore \frac{5}{13}$ part of the chocolate cake would be left now.