Question

Calcule as expressões numéricas:

a) 5/4 × (1/2)² + 5/7 ÷ 15/2 =_____

b) [ 31/400 + (1/4 + 2/5)² ] × 2 =______

por favor ! me ajuda.​

Answer 1

Resposta:

Explicação passo-a-passo:

Calcule as expressões numéricas:

a) 5/4 × (1/2)² + 5/7 ÷ 15/2 =_____

= 5/4 . 1/4 + 5/7 . 2/15

= 5/16 + 5/15 (:5)/(:5) . 2/7

= 5/16 + 1/3 . 2/7

= 5/16 + 2/21

Mmc = 16.21

Mmc = 336

= (21.5 + 16.2)/336

= (105+32)/336

= 137/336

R.: 137/336

____________

Obs.: mmc (16,21)

16,21: 2

8,21: 2

4, 21: 2

2, 21: 2

1, 21: 3

1,7: 7

1,1

= 2^4.3.7

= 16.21

= 336

b) [ 31/400 + (1/4 + 2/5)² ] × 2 =

= {31/400 + [(5+4.2)/20]^2} . 2

= {31/400 + [(5+8)/20]^2} . 2

= {31/400 + [13/20]^2}.2

= {31/400 + 169/400}.2

= {200/400}.2

= 2/4 . 2

= 4/4

= 1

R.: 1