Decide what values of the variable cannot possibly be solutions for the equation.
-One maid can clean the house in 5 hours. Another maid can do the job in 3 hours. How long will it take them to do the job working together?
A) $\frac { 1 } { 15 } \mathrm { hr }$
B) $\frac { 15 } { 8 } \mathrm { hr }$
C) $\frac { 15 } { 2 } \mathrm { hr }$
D) $\frac { 1 } { 8 } \mathrm { hr }$

Question

Decide what values of the variable cannot possibly be solutions for the equation.
-One maid can clean the house in 5 hours. Another maid can do the job in 3 hours. How long will it take them to do the job working together? 
A) $\frac { 1 } { 15 } \mathrm { hr }$
B) $\frac { 15 } { 8 } \mathrm { hr }$
C) $\frac { 15 } { 2 } \mathrm { hr }$
D) $\frac { 1 } { 8 } \mathrm { hr }$

Quizplus · Accepted Answer

The correct answer is found by adding the rates of the two maids working together: $ \frac{1}{5} + \frac{1}{3} = \frac{3}{15} + \frac{5}{15} = \frac{8}{15} $ hours. To find the time it takes for them to complete the job together, take the reciprocal of this sum, which gives $ \frac{15}{8} $ hours.

Decide What Values of the Variable Cannot Possibly Be Solutions 115hr\frac { 1 } { 15 } \mathrm { hr }151​hr

Decide What Values of the Variable Cannot Possibly Be Solutions $\frac { 1 } { 15 } \mathrm { hr }$