HOTs for Maths Olympiad - 5 - Class 5 MCQ

The greatest 3-digit number is 999.

The smallest 2-digit number is 10.

Now, calculate the product:

999 × 10 = 9990

Thus, the correct product is 9990.

The correct answer is A: 9990.

To calculate the time taken to cover a distance, we use the formula:
Time = Distance ÷ Speed
Given:

Distance = 300 km

Speed = 60 km/h

Now, calculate the time: 300 km ÷ 60 km/h = 5 hours.
Thus, the time taken to cover 300 km is 5 hours. Therefore, the correct answer is B: 5 hours.

The first five multiples of 7 are: 7, 14, 21, 28, and 35.

The sum of these multiples can be calculated as follows:

• 7 + 14 = 21
• 21 + 21 = 42
• 42 + 28 = 70
• 70 + 35 = 105

Therefore, the total sum is 105.

Total number of students in the class = 45

The fraction of boys in the class = 3/5

First, calculate the number of boys in the class:

Number of boys = (3/5) × 45 = 27 boys

Now, calculate the number of girls in the class by subtracting the number of boys from the total number of students:

Number of girls = 45 - 27 = 18 girls

Thus, the number of girls in the class is 18. Therefore, the correct answer is A: 18.

To find the Least Common Multiple (LCM) of 8, 12, and 16, we can use the prime factorization method.

Prime factorization:

• 8 = 2³
• 12 = 2² × 3
• 16 = 2⁴

To find the LCM, we take the highest power of each prime factor:

• The highest power of 2 is 2⁴.
• The highest power of 3 is 3.

Now, multiply these highest powers together: LCM = 2⁴ × 3 = 16 × 3 = 48

Thus, the LCM of 8, 12, and 16 is 48. Therefore, the correct answer is C: 48.

The formula for the perimeter of a square is:

Perimeter = 4 × side length

Given that the perimeter is 36 cm, we can set up the equation:

36 = 4 × side length

Now, solve for the side length:

side length = 36/4 = 9 cm

Thus, the length of each side is 9 cm.
Therefore, the correct answer is B: 9 cm.

The formula for speed is:
Speed = Distance ÷ Time

To find the speed of the car:

• Distance: 150 km
• Time: 3 hours

Now, calculate the speed:

Speed = 150 km ÷ 3 hours = 50 km/h

The correct answer is 50 km/h.

The sum of the angles in any triangle is always 180°.

This means that if you add up the three interior angles of a triangle, the total will always equal 180°.

• For example, in a triangle with angles of 60°, 60°, and 60°, the sum is 180°.
• In another triangle with angles of 30°, 60°, and 90°, the sum is also 180°.

Therefore, the correct answer is 180°.

Length of each part = Total length ÷ Number of parts

Original length of the rope: 56 meters

Number of parts: 4

Calculation: Length of each part = 56 meters ÷ 4

Result: Length of each part = 14 meters

The correct answer is 14 meters.

To find the number of fruits to be put in each basket in order to have the minimum number of baskets, we need to find the greatest common divisor (GCD) of the number of apples (990) and the number of oranges (945). This will ensure that the fruits are packed in equal numbers in each basket while minimizing the number of baskets.

Prime factorization:

990 = 2 × 3² × 5 × 11

945 = 3³ × 5 × 7

Finding the GCD:

The common factors are 3² and 5, so the GCD is:
GCD = 3² × 5 = 9 × 5 = 45
The number of fruits to be put in each basket in order to minimize the number of baskets is 45. This means each basket will contain 45 apples or 45 oranges.

Thus, the correct answer is 45 fruits.