Question

The HCF and LCM of two numbers x and y is 6 and 210 respectively. If x + y = 72, which of following relation is correct?​

• A. $\frac{1}{x}$ + $\frac{1}{y}$ = $\frac{3}{35}$
• B. $\frac{1}{x}$ + $\frac{1}{y}$ = $\frac{2}{35}$
• C. $\frac{1}{x}$ + $\frac{1}{y}$ = $\frac{35}{2}$
• D. $\frac{1}{x}$ + $\frac{1}{y}$ = $\frac{35}{3}$

Answer 1

The correct option is B $\frac{1}{x}$ + $\frac{1}{y}$ = $\frac{2}{35}$

x x y = LCM x HCF = 6 x 210
$\frac{1}{x}$ + $\frac{1}{y}$ = $\frac{y+x}{xy}$ = $\frac{72}{210\times 6}$ = $\frac{2}{35}$