Solve the Equation $\frac { b } { 35 } + \frac { b } { 56 } = 1$

Multiple Choice

Solve the equation. $\frac { b } { 35 } + \frac { b } { 56 } = 1$

A) b = 280
B) $b = \frac { 13 } { 280 }$
C) $b = 21 \frac { 7 } { 13 }$
D) b = 13