Playing with Numbers - A

The traffic lights at three different road crossings change after every 48 seconds, 72 seconds and 108 seconds respectively. If they change simultaneously at 7 a.m., at what time will they change simultaneously again?

• After 7 min

• After 7 min 12 sec

• After 7 min 48 sec

• After 7 min 52 sec

WHICH OF THE FOLLOWING IS THE FACTOR PAIR OF 84?

• 2 AND 21

• 6 AND 14

• 3 AND 36

• 9 AND 7

THE FOLLOWING NUMBERS ARE ALL __________OF 7?

7,14,21,28,35,42,49,56.........

• ANSWERS

• NUMBERS

• FACTORS

• MULTIPLES

WHICH OF THE FOLLOWING IS PRIME NUMBERS?

• 191

• 82

• 54

• 343

Which of the following pairs is co-primes

• (20,25)

• ( 45, 54)

• (16,21)

• (30,33)

Is 7320 divisible by 6 ?

• Yes

• No

Is 198704 divisible by 11 ?

• Yes

• No

The prime factorisation of 96 is

• 2×2×2×3×3

• 2×2×2×3×4

• 2×2×2×2×3×3

• 2×2×2×2×2×3

HCF of two even numbers is

• 0

• 1

• 2

• 3

Which of the following number is divisible by 3 but not by 9?

• 810
• 270
• 330
• 450