Problema Solution
Angelo runs 7 miles per week and increases his distance by 1 mile each week. after how many weeks, will Angelo be running 12 miles per week?
Answer provided by our tutors
first week Angelo runs 7 mi:
x1 = 7
second week he increases by 1:
x2 = x1 + 1
third week:
x3 = x2 + 1 = x1 + 1 + 1 = x1 + 2*1
4th week:
x4 = x3 + 1 = x1 + 2*1 + 1 = x1 + 3*1
nth week:
xn = x1 + (n-1)*1
xn = 7 + (n - 1)
xn = 6 + n
now lets find n such that xn = 12
6 + n = 12
n = 12 - 6
n = 6
the 6th week Angelo will be running 12 miles.