Brian can lay a slab of concrete in 6 hours, while greg can do it in 4 hours. if brian and greg work together, how long will it take?

Step-by-step explanation:

we know that

step 1

Brian can lay a slab of concrete in 6 hours

so

The 100% -------> in 6 hours

using proportion

Find in an hour how much percentage  Brian can execute

step 2

Greg can lay a slab of concrete in 4 hours

so

The 100% -------> in 4 hours

using proportion

Find in an hour how much percentage  Greg can execute

step 3

we know that

In one hour (Brian and Greg) execute (16.67%+25%)=41.67%

so

by proportion

Find out how long it will take Brian and Greg to lay a concrete slab working together

step-by-step explanation:

step-by-step explanation:

let's assume

number of candles set =x

price of of x candles =p(x)

we are given

a candle maker prices one set of scented candles at $10 and sells an average of 200 sets each week

so, we get point as (200,10)

he finds that when he reduces the price by $1, he then sells 50 more candle sets each week

so, we can find slope

now, we can use point slope form of line

now, we can plug values

we can use point

and find b

now, we can plug it back

and we get

now, we can find revenue

we know that

revenue = price*quantity

so, we get