The Extreme Rock Climbing Club planned a climbing expedition. The total cost was $1400, which was to be divided equally among the members going. Prior to the trip, 3 members decided not to go. If the cost per person increased by $105, how many people went on the expedition?

To find the rate per person, we divide the additional $105 by the three people who backed out. The quotient would be 35. Hence, each person should pay $35. To determine how many people went to the expedition, divide the $1400 + $105 by 35, the answer is 43. Since 3 backed out, then the total number who actually went was 40.