What is the estimated mean28-day strength of this concrete if the 7-day strength is 3000psi?

12,000psi

Step-by-step explanation:

Given the 7 days strength of a concrete to be 3000psi, to calculate the estimated mean28-day strength of this concrete the following equality equation is applied

7 days strength = 3000psi

28days strength = y

To get y, we will Cross multiply

7 × y = 28×3000

7y = 28×3000

7y = 84000

Divide both sides by 7

7y/7 = 84000/7

y = 12000

hence the estimated mean 28-day strength of this concrete is 12,000psi

the answer is y = 11.54

hope this : )

she was supposed to add the hours(38.5) and multiply the amount of money she earned(7.50) resulting in $288.75 .

correct me if i'm wrong and if it is i'm truly sorry.