Grade 7 Mathematics worksheet
1. (a) Use index notation to express each of the following numbers as a product of
prime factors.
(i) 18
Answer: 18 = 2 × 3²
(ii) 24
Answer: 24 = 2³ × 3
(b) Hence, find the H.C.F. and L.C.M. of 18 and 24.
Answer:
o H.C.F. = 2 × 3 = 6
o L.C.M. = 2³ × 3² = 72
2. Compare the numbers in each of the following groups, and use ‘>’ or ‘<’ to
express the answers.
3 2
− +
(a) 2 _______ 3
(a) Answer: <
(b) +4 _______ −0.4
(b) Answer: >
1 1
− −
(c) 8 _______ 18
(c) Answer: <
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1. (a) Use index notation to express each of the following numbers as a product of
prime factors.
(i) 18
Answer: 18 = 2 × 3²
(ii) 24
Answer: 24 = 2³ × 3
(b) Hence, find the H.C.F. and L.C.M. of 18 and 24.
Answer:
o H.C.F. = 2 × 3 = 6
o L.C.M. = 2³ × 3² = 72
2. Compare the numbers in each of the following groups, and use ‘>’ or ‘<’ to
express the answers.
3 2
− +
(a) 2 _______ 3
(a) Answer: <
(b) +4 _______ −0.4
(b) Answer: >
1 1
− −
(c) 8 _______ 18
(c) Answer: <
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