[ESH] Math Race 2024

Seventy days after the day before yesterday is Friday. Which day of the week is tomorrow?

• • Monday

• • Saturday

• • Sunday

• • Thursday

Answer explanation

70 days is exactly 10 weeks. 10 weeks after the day before yesterday is Friday. Hence the day before yesterday is also Friday, yesterday is Saturday, today is Sunday, and tomorrow is Monday.

In a school, 52 students were given vouchers for a bookstore or cafeteria. Twenty of them received bookstore vouchers and 39 students received cafeteria vouchers. How many students received both vouchers?

• 7

• 8

• 9

• 10

Answer explanation

20 + 39 = 59 vouchers were given 59 – 52 = 7 students received both vouchers

Find the missing shape in the pattern.

• 
• 
• 
• 

Answer explanation

A cube is a solid consisting of identical squares. A cube has 6 faces. A “dodecahedron” is a solid consisting of identical pentagons (5-sided shapes), as illustrated below. If a dodecahedron has 12 faces, how many edges does it have?

• 5

• 20

• 12

• 30

Answer explanation

Each face has 5 edges. Then

12 faces x 5 edges = 60 edges.

However, every edge has been counted twice as there are 2 faces sharing the same edge. Thus, a dodecahedron has

60 ÷ 2 = 30 edges.

Clayton gave 77 baseball cards to his friend and 112 baseball cards to his brother. In the end, Clayton is left with 441 baseball cards. What percentage of his original number of cards did Clayton give away?

• • 70%

• • 60%

• • 40%

• • 30%

Answer explanation

The number of cards Clayton gave away is

77 + 112 = 189. His original number of cards was

189 + 441 = 630.

Hence the percentage is 189 : 630 x 100 = 30%.

Each of the 3-digit numbers 𝐴𝐵𝐶, 𝐵𝐶𝐴 and 𝐶𝐴𝐵 is even and divisible by 9. If 𝐴, 𝐵 and 𝐶 are different digits, find the value of 𝐴 + 𝐵 + 𝐶.

• 18

• 9

• 20

• 12

Answer explanation

The digits 𝐴, 𝐵 and 𝐶 are even since 𝐴𝐵𝐶, 𝐵𝐶𝐴 and 𝐶𝐴𝐵 are even. Using the divisibility test for 9, the sum of digits 𝐴 + 𝐵 + 𝐶 is divisible by 9. Since the digits 𝐴, 𝐵 and 𝐶 are even, then 𝐴 + 𝐵 + 𝐶 = 18.

How many rectangles (including squares) are there in the figure below?

• 44

• 40

• 38

• 36