A bricklayer can build a wall of a certain size in 5 hours. Another bricklayer can do the same job in 4 hours. If the bricklayers work together, how long would it take to do the job?
a. 9h
b. 2(2/9)h
c. 20h
d. 4(1/2)h

Respuesta :

Answer:

b

Step-by-step explanation:

It will take [tex]\frac{20}{9}[/tex] hours as per linear equation to complete the wall.

What is a linear equation?

A linear equation is an equation where the variable of the equation has the highest power of degree one.

Given, the 1st bricklayer build a complete wall of certain size in 5 hours.

Therefore, that bricklayer build [tex]\frac{1}{5}[/tex]th of the complete wall in 1 hour.

Similarly, the 2nd bricklayer build a complete wall of certain size in 4 hours.

Therefore, that bricklayer build [tex]\frac{1}{4}[/tex]th of the complete wall in 1 hour.

If they work together, in 1 hour they build a total of ([tex]\frac{1}{5}[/tex]+[tex]\frac{1}{4}[/tex])th = [tex]\frac{9}{20}[/tex] of the complete wall.

Hence, they will complete the wall in (1÷[tex]\frac{9}{20}[/tex]) hours = [tex]\frac{20}{9}[/tex] hours.

Learn more about a linear equation here: https://brainly.com/question/13738061

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