Answer:
x = 2
Step-by-step explanation:
x = 
= 
= 
= 2
Both sides are identical.
n(A-B) denotes elements which are in A but not in B
n(Au B) denotes elements in A and B
n(AnB) denotes elements that are common in A and B
Now I will add one more set
n(B-A) which denotes elements in B but not in A
So, n(AuB) = n(A-B) + n( B-A) +n(AnB)
70 = 18 +n(B-A) + 25
70 = 43 + n(B-A)
n(B-A) = 70-43
n(B-A) = 27
So, n(B) = n( B-A) + n( AnB)
= 27+25
= 52
Answer:
Step-by-step explanation:
You have to set each runner's plan equal to each other because they are equal in the end. You start with 7 miles for Angelo and 4 miles for Marc.
x is a variable that is multiplied by the number of weeks it takes for both runners' distances to be equal. So multiply x by the miles increased every week.
Marc = Angelo
2x + 4 = x + 7
x = 3
In 3 weeks each runner will run 10 miles for the week.
