Răspuns:
Explicație pas cu pas:
237.
prima floare este rezolvata in model
a doua floare 6 x 6 = 36; 9 x 4 = 36
a treia floare 8 x 5 = 40; 10 x 4 = 40
a patra floare 15 x 2 = 30; 5 x 6 = 30
238.
35 = 5 x 7
36 = 3 x 12
42 = 6 x 7
48 = 6 x 8
56 = 8 x 7
72 = 9 x 8
80 = 8 x 10
239.
5 x (4 + 3) = 5 x 7 = 35
5 x (4 + 3) = 5 x 4 + 5 x 3 = 20 + 15 = 35
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3 x (4 + 4) = 3 x 8 = 24
3 x (4 + 4) = 3 x 4 + 3 x 4 = 12 + 12 = 24
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4 x (9 + 1) = 4 x 10 = 40
4 x (9 + 1) = 4 x 9 + 4 x 1 = 36 + 4 = 40
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10 x (3 + 6) = 10 x 9 = 90
10 x (3 + 6) = 10 x 3 + 10 x 6 = 30 + 60 = 90
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2 x (3 + 5 + 1) = 2 x 9 = 18
2 x (3 + 5 + 1) = 2 x 3 + 2 x 5 + 2 x 1 = 6 + 10 + 2 = 18
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3 x (3 + 5 + 2) = 3 x 10 = 30
3 x (3 + 5 + 2) = 3 x 3 + 3 x 5 + 3 x 2 = 9 + 15 + 6 = 30
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(7 + 3) x 5 = 10 x 5 = 50
(7 + 3) x 5 = 7 x 5 + 3 x 5 = 35 + 15 = 50
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(5 + 4) x 6 = 9 x 6 = 54
(5 + 4) x 6 = 5 x 6 + 4 x 6 = 30 + 24 = 54
