Answer:
her first mistake was on line 3.
line 1: 80 + [2(3 1/2 + 1 1/2)]
line 2: 80 + [2(5)]
line 3: 80 + 10
line 4: 90
Step-by-step explanation:
on line 3 she added 80 + 2, but she should have multiplied 2 by 5. the correct steps would be:
line 1: 80 + [2(3 1/2 + 1 1/2)]
line 2: 80 + [2(5)]
line 3: 80 + 10
line 4: 90
3 4
—- = —-
x 5
cross multiply 3 and 5 = 15
and 4 and x = 4x
you get 15=4x
x= 15/4
It is a 50 percent chance. This is because there is only two possibilities that can occur. It does not matter how many times the coin has been flipped.