Question

8 cleaners can clean an office in 3 hours,if the block needs to be cleaned in 2 hours,how many cleaners will be needed?

Answer 1

Answer:

12 cleaners

Step-by-step explanation:

8 cleaner can clean in 3 hours = 1 office

1 cleaner can clean in 3 hours = $\frac{1}{8}$  part of job

1 cleaner can clean in 1 hours = $\frac{1}{3 \times 8}$  part of job

Let the number of cleaner required to finish the job in 2 hours = x

hence

x cleaner can clean in 1 hours = $\frac{1 \times x }{24}$  part of job

x cleaner can clean in 2 hours = $\frac{2 \times x }{24}$  part of job

Hence

$\frac{2 \times x }{24}=1$

$\frac{2x}{24}=1$

$2x=24$

$x=12$

Hence we need 12 men to complete the same job in 2 hours