ISAT - International Student Admissions Mathematical Problem-Solving 2

Question 1

A cylindrical tank: radius 3m, height 5m. Pump rate: 2 cubic meters/min. Time to fill to 80%? (pi=3.14)

Accepted Answer

56.5 minutes

Answer

45.2 minutes

Answer

70.7 minutes

Answer

35.3 minutes

Question 2

Blend A: $12/kg. Blend B: $8/kg. Want 5kg at $9.60/kg. How much of each?

Accepted Answer

2 kg A, 3 kg B

Answer

3 kg A, 2 kg B

Answer

2.5 kg each

Answer

1.5 kg A, 3.5 kg B

Question 3

Revenue function R(x) = -2x^2 + 120x - 400. How many units (thousands) maximize revenue?

Accepted Answer

30,000 units; $1,400

Answer

40,000 units; $1,200

Answer

25,000 units; $1,350

Answer

35,000 units; $1,050

Question 4

Anna pays 1/3 of a dinner bill, Ben pays 1/4. Carla pays the remaining $25. What was the total?

Accepted Answer

$60

Answer

$50

Answer

$75

Answer

$45

Question 5

A boat: 24km upstream in 3 hours, 24km downstream in 2 hours. Find boat speed and current speed.

Accepted Answer

Boat: 10 km/h, Current: 2 km/h

Answer

Boat: 12, Current: 4

Answer

Boat: 8, Current: 4

Answer

Boat: 10, Current: 4

Question 6

Rectangular prism: 8cm x 6cm x 4cm. What is the space diagonal length?

Accepted Answer

sqrt(116) = 10.8 cm

Answer

sqrt(100) = 10 cm

Answer

sqrt(80) = 8.9 cm

Answer

sqrt(136) = 11.7 cm