model 3 find hcf of numbers Section-Wise Topic Notes With Detailed Explanation And Example Questions

Answer: (d)

As the height of each stack is same,

the required number of books in each stack

= HCF of 84, 90 and 120

84 = 2 × 2 × 3 × 7

90 = 2 × 3 × 3 × 5

120 = 2 × 2 × 2 × 3 × 5

∴ HCF = 2 × 3 = 6

Answer: (c)

Using Rule 7,

The greatest number N = HCF of (1305 – x ), (4665 – x ) and (6905 – x),

where x is the remainder

= HCF of (4665 – 1305), (6905– 4665) and (6905 – 1305)

= HCF of 3360, 2240 and 5600

∴ N = 1120

Sum of digits = 1 + 1 + 2 + 0 = 4

Answer: (d)

Minimum number of rows = Maximum number of fruits in each row

∴ HCF of 24, 36 and 60 = 12

∴ Minimum number of rows

= $24/12 + 36/12 + 60/12$

= 2 + 3 + 5 = 10

Answer: (d)

HCF of numbers = 12

Let the numbers be 12x and 12y

where x and y are co–prime.

According to the question,

12x × 12y = 2160

⇒ xy = $2160/{ 12×12}$ = 15

= 3 × 5 or 1 × 15

∴ Required numbers

= 12 × 3 = 36 and 12 × 5 = 60