Question

8дм-30см= 70см-5дм= 5дм+4см= 6дм+30см=

Answer 1

1дм = 10 см

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10 * 8 - 30 = 80 - 30 = 50см

70 - 5 * 10 = 70 - 50 = 20см

10 * 5 + 4 = 50 + 4 = 54см

10 * 6 + 30 = 60 + 30 = 90см