A) 14 cms | B) 21 cms |

C) 42 cms | D) None of these |

Explanation:

3.78 meters =378 cm = 2 × 3 × 3 × 3 × 7

5.25 meters=525 cm = 5 × 5 × 3 × 7

Hence common factors are 3 and 7

Hence LCM = 3 × 7 = 21

Hence largest size of square tiles that can be paved exactly with square tiles is 21 cm.

A) 63 and 49 | B) 64 and 48 |

C) 62 and 46 | D) 64 and 49 |

Explanation:

Since their HCFs are 7, numbers are divisible by 7 and are of the form 7x and 7y

Difference = 14

=> 7x - 7y = 14

=> x - y = 2

product of numbers = product of their hcf and lcm

=> 7x * 7y = 441 * 7

=> x * y = 63

Now, we have

x * y = 63 , x - y = 2

=> x = 9 , y = 7

The numbers are 7x and 7y

=> 63 and 49

A) 13/125 | B) 14/57 |

C) 11/120 | D) 16/41 |

Explanation:

Let the numbers be a and b.

We know that product of two numbers = Product of their HCF and LCM

Then, a + b = 55 and ab = 5 x 120 = 600.

=> The required sum = (1/a) + (1/b) = (a+b)/ab

=55/600 = 11/120

A) 7 lts | B) 14 lts |

C) 98 lts | D) 42 lts |

Explanation:

To know the the measuring cylinder that can fill all the given capacities , they must be divisible by the required number.

98,182,266 all are divisible by 14

So 14 litres is the largest cylinder that can fill all the given cylinders.

(or)

The other method is take HCF of all given capacities i.e 98, 182 and 266.

A) 6 | B) 8 |

C) 4 | D) 9 |

Explanation:

N = H.C.F. of (4665 - 1305), (6905 - 4665) and (6905 - 1305)

= H.C.F. of 3360, 2240 and 5600 = 1120.

Sum of digits in N = ( 1 + 1 + 2 + 0 ) = 4

A) 64 | B) 69 |

C) 71 | D) 58 |

Explanation:

To find the greatest number which divides the numbers 964, 1238 and 1400 leaving the remainders 41, 31 and 51 is nothing but the HCF of (964 - 41), (1238 - 31), (1400 - 51).

Therefore, HCF of 923, 1207 and 1349 is 71.