CAEC Mathematics Preparation Course: Number sense: money, percentages, rates and ratios

1. Pregunta 1 de 17

   Your restaurant bill is $64.00. You want to leave a 15% tip. How much is the tip?

   • A$96.00
   • B$73.60
   • C$9.60
   • D$6.40
   Ver respuesta

   Respuesta: C. $9.60

   15% of $64.00 = 0.15 × 64 = $9.60.

2. Pregunta 2 de 17

   A jacket costs $120. It is on sale for 25% off. What is the sale price?

   • A$30.00
   • B$90.00
   • C$150.00
   • D$95.00
   Ver respuesta

   Respuesta: B. $90.00

   The discount is 25% of $120 = $30. The sale price is $120 − $30 = $90.00.

3. Pregunta 3 de 17

   An item costs $80.00 before tax. A 5% tax is added. What is the total?

   • A$80.40
   • B$85.00
   • C$84.00
   • D$4.00
   Ver respuesta

   Respuesta: C. $84.00

   Tax = 5% of $80 = $4.00. Total = $80 + $4 = $84.00.

4. Pregunta 4 de 17

   Boots cost $200. They are 30% off, and then a 5% tax is added to the sale price. What do you pay?

   • A$140.00
   • B$147.00
   • C$63.00
   • D$150.00
   Ver respuesta

   Respuesta: B. $147.00

   Sale price = $200 × 0.70 = $140. Add 5% tax: $140 × 1.05 = $147.00.

5. Pregunta 5 de 17

   A salesperson earns a 4% commission. She sells $8,500 of furniture. How much commission does she earn?

   • A$34.00
   • B$3,400.00
   • C$8,840.00
   • D$340.00
   Ver respuesta

   Respuesta: D. $340.00

   4% of $8,500 = 0.04 × 8,500 = $340.00.

6. Pregunta 6 de 17

   You earn $18.50 an hour and work 37.5 hours a week. What is your weekly pay before deductions?

   • A$693.75
   • B$740.00
   • C$56.00
   • D$684.50
   Ver respuesta

   Respuesta: A. $693.75

   Pay = rate × hours = $18.50 × 37.5 = $693.75.

7. Pregunta 7 de 17

   You earn $20 an hour for the first 40 hours and 1.5 times that rate for overtime. This week you worked 46 hours. What is your pay?

   • A$920.00
   • B$1,380.00
   • C$980.00
   • D$830.00
   Ver respuesta

   Respuesta: C. $980.00

   Regular pay: 40 × $20 = $800. Overtime rate: $20 × 1.5 = $30, and 6 × $30 = $180. Total: $980.00.

8. Pregunta 8 de 17

   You put $2,000 in a savings account that pays 3% simple interest per year. How much interest do you earn in 4 years?

   • A$2,240.00
   • B$60.00
   • C$24.00
   • D$240.00
   Ver respuesta

   Respuesta: D. $240.00

   Simple interest I = Prt = $2,000 × 0.03 × 4 = $240.00.

9. Pregunta 9 de 17

   You borrow $1,500 at 6% simple interest per year for 18 months. How much do you pay back in total?

   • A$1,590.00
   • B$1,635.00
   • C$3,120.00
   • D$135.00
   Ver respuesta

   Respuesta: B. $1,635.00

   Time must be in years: 18 months = 1.5 years. I = $1,500 × 0.06 × 1.5 = $135. Total = $1,500 + $135 = $1,635.00.

10. Pregunta 10 de 17

    Milk costs $4.20 for 1.5 L or $5.30 for 2 L. Which is the better buy, and what is its price per litre?

    • AThe 1.5 L size, at $2.80 per litre
    • BThe 1.5 L size, at $2.65 per litre
    • CThe 2 L size, at $2.80 per litre
    • DThe 2 L size, at $2.65 per litre
    Ver respuesta

    Respuesta: D. The 2 L size, at $2.65 per litre

    Unit price = price ÷ litres. $4.20 ÷ 1.5 = $2.80 per litre; $5.30 ÷ 2 = $2.65 per litre. The 2 L size costs less per litre.

11. Pregunta 11 de 17

    You drive at an average speed of 90 km/h. How long does a 405 km trip take?

    • A4 h 30 min
    • B4 h 50 min
    • C4 h 5 min
    • D5 h 30 min
    Ver respuesta

    Respuesta: A. 4 h 30 min

    Time = distance ÷ speed = 405 ÷ 90 = 4.5 hours. 0.5 hours is 30 minutes, so 4 h 30 min.

12. Pregunta 12 de 17

    Juice is mixed 1 part concentrate to 4 parts water. How much concentrate do you need to make 2.5 L of juice?

    • A0.5 L
    • B0.625 L
    • C10 L
    • D2 L
    Ver respuesta

    Respuesta: A. 0.5 L

    1 + 4 = 5 parts in total. Each part is 2.5 L ÷ 5 = 0.5 L, and concentrate is 1 part, so 0.5 L.

13. Pregunta 13 de 17

    A recipe for 4 people uses 300 g of pasta. How much pasta do you need for 10 people?

    • A1,200 g
    • B3,000 g
    • C750 g
    • D600 g
    Ver respuesta

    Respuesta: C. 750 g

    Pasta per person = 300 ÷ 4 = 75 g. For 10 people: 75 × 10 = 750 g.

14. Pregunta 14 de 17

    A map has a scale of 1 : 50 000. Two towns are 6 cm apart on the map. How far apart are they in real life?

    • A0.3 km
    • B30 km
    • C300 km
    • D3 km
    Ver respuesta

    Respuesta: D. 3 km

    6 cm × 50 000 = 300 000 cm. 100 000 cm = 1 km, so the distance is 3 km.

15. Pregunta 15 de 17

    Monthly rent goes up from $1,400 to $1,505. What is the percent increase?

    • A7.5%
    • B7%
    • C0.75%
    • D105%
    Ver respuesta

    Respuesta: A. 7.5%

    Percent change = change ÷ original × 100. The change is $105, and $105 ÷ $1,400 × 100 = 7.5%.

16. Pregunta 16 de 17

    Your car uses 8.5 L of fuel per 100 km. Fuel costs $1.55 per litre. What does fuel cost for a 340 km trip?

    • A$4,479.50
    • B$13.18
    • C$28.90
    • D$44.80
    Ver respuesta

    Respuesta: D. $44.80

    Fuel used = 8.5 × 340 ÷ 100 = 28.9 L. Cost = 28.9 × $1.55 = $44.795, which rounds to $44.80.

17. Pregunta 17 de 17

    The sheet shows a monthly budget. Cell B2 is the take-home pay. How much money is left after all the costs in B3 to B7 are paid?

    	A	B
    1	Item	Amount ($)
    2	Take-home pay	3200.00
    3	Rent	1450.00
    4	Groceries	615.40
    5	Transit pass	120.00
    6	Phone	85.25
    7	Utilities	210.00

    • A$719.35
    • B$1,750.00
    • C$2,480.65
    • D$929.35
    Ver respuesta

    Respuesta: A. $719.35

    Total costs = 1,450 + 615.40 + 120 + 85.25 + 210 = $2,480.65. Left over = $3,200.00 − $2,480.65 = $719.35.

Teclado: 1–4 para responder, Intro para la siguiente pregunta.

El examen real: 55% on each CAEC test