Rule Three Exercises

a) Three trucks transport 200m³ of sand. To transport 1600m³ of sand, how many trucks would it take?

b) The food left for 3 castaways would be enough to feed them for 12 days. One of them decided to jump and try to land ashore swimming. With one less castaway, how long will the food be?

c) To answer all calls made to a company, 3 telephone operators are used, each answering an average of 125 calls per day. If we increase the number of operators to 5, how many calls will each day answer on average?

d) A painter, working 8 hours a day for 10 days, paints 7,500 tiles. How many hours a day should this painter work so that he can paint 6,000 tiles in 4 days?

e) In a shooting match, a catapult, operating for 6 batteries of 15 minutes each, throws 300 stones. How many stones will you throw in 10 batteries of 12 minutes each?

f) Ten mobile cranes carry 200 boxes on a ship within 18 days of 8 working hours. How many boxes will be loaded in 15 days by 6 cranes working 6 hours a day?

g) At a speed of 75 km / h, a bus travels in 40 min. Due to a traffic jam, this bus made the return trip in 50 min. What is the average speed of this bus?

h) Knowing that the numbers The, 12 and 15 are directly proportional to the numbers 28, B and 20, determine the numbers The and B.

i) A 1.5 m long plank was placed vertically from the floor and cast a shadow of 53 cm. What would be the shadow cast at the same time by a pole that is 10.5 m high?

j) A certain amount of juice was placed in 2 liter cans each, thus obtaining 60 cans. If 3-liter cans were used, how many cans would it take to pour the same amount of juice?