**Q22.** Which of the following is a pair of co-primes?

A. (23, 92) |
B. (16, 62) |

C. (21, 35) |
D. (18, 25) |

**Q23.** The product of the L.C.M. and H.C.F. of two numbers is 24. The difference of two numbers is 2. Find the numbers.

A. 6 and 4 |
B. 8 and 6 |

C. 8 and 10 |
D. 2 and 4 |

**Q24.** The L.C.M. of three different numbers is 120. Which of the following cannot be their H.C.F.?

A. 8 |
B. 24 |

C. 35 |
D. 12 |

**Q25.** H.C.F. of 3240, 3600 and a third number is 36 and their L.C.M is 2^{4} x 3^{5} x 5^{2} x 7^{2}. The third number is:

A. 2^{5} x 5^{2} x 7^{2} |
B. 2^{2} x 3^{5} x 7^{2} |

C. 2^{2} x 5^{3} x 7^{2} |
D. 2^{3} x 3^{5} x 7^{2} |