Q. Solve the following (try to solve mentally):
a) 4 4 5 6
– 3 7 1 7
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b) 1 8 1 6
– 1 7 1 9
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c) 6 4 3 8
– 2 8 4 6
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d) 8 3 2 3
– 1 8 2 1
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e) 8 8 4 6
– 2 7 1 9
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f) 9 1 6
– 6 6 7
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g) 5 2 9 3
– 9 3 3 4
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h) 4 9 4 4
– 1 2 3 4
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i) 4 5 3 6
– 3 6 5 4
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