One bricklayer can build a wall in 6 hours. another bricklayer could build the same wall in 4 hours. if they work together, how long will it take to build the wall?

they work together, it will take 2.4 hours to build the wall.

Step-by-step explanation:

One bricklayer can build a wall in 6 hours.

One hour work =

Another bricklayer can build the same wall in 4 hours.

One hour work =

They can together, how long will take them to build the wall.

Let's take "t" the time taken to build the wall.

The sum of their work rate = 1 (To build the wall)

Now we have to solve this equation. Take LCD of 6 and 4.

The LCD (least common divisor) of 6 and 4 is 12.

5t = 12*1

5t = 12

Dividing both sides by 5, we get

t =

t = 2.4 hours.

So, they work together, it will take 2.4 hours to build the wall.

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explanation

the graph has a slope of 1/3 because each time you move up 1, you go to the right 3. so, slope = rise/run = 1/3. we can cross choice a off the list since we want a slope of 3, rather than 1/3.

the first table shown has a slope of -3. this is because the rise is -6 and the run is 2, so slope = rise/run = -6/2 = -3. note how x increases by 2 each time (run) and y drops by 6 each time (rise). choice b can be eliminated.

the second table has a slope of 3. each time x goes up by 1, the y values increase by 3. slope = rise/run = 3/1 = 3. alternatively you can use the slope formula to prove that the slope is 3 here. use any two rows of values to generate the two points. choice c is one of the answers

the third table also has a slope of 3. let's use the slope formula to prove as such. i'm going to use the first two rows of the table. so i'll use the two points (2,1) and (5,10)

m = slope

m = (y2-y1)/(x2-x1)

m = (10-1)/(5-2)

m = 9/3

m = 3 so we get a slope of 3

choice d is the other answer

if x decreases by 4 then y increases by 10

step-by-step explanation: