Номера 12,19,20Даю 20 баллов

Question

Номера 12,19,20
Даю 20 баллов

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Comments

Помогите срочно

Answer 1

12) 3.24-2.1312=1.1088
1.1088÷0.42=2.64
7.2×3.8=27.36
27.36+2.64=30
19) 2.04-1 1/4=2.04-1.25=0.79
0.79÷1/20=79/100×20/1=79/5=15 4/5
20) 3.42-2 5/8=3 42/100-2 5/8=3 168/400- 2 250/400=318/400=159/200
159/200÷1/50=159/200×50/1=159/4=39 3/4