Question

2- Calcule.
a) 10% de 200
b) 50% de 450
c) 20% de 40
d) 30% de 50
e) 40% de 90

Answer 1

Resposta:

> Utilizando a Regra de Três.

a) 10% de 200

200--------------100%

x-------------------10%

100x = 200 . 10

100x = 2000

x = 2000÷100

x = 20

b) 50% de 450

450-----------------100%

x---------------------50%

100x = 450 . 50

100x = 22500

x = 22500÷100

x = 225

c) 20% de 40

40------------------100%

x--------------------20%

100x = 40 . 20

100x = 800

x = 800÷100

x = 8

d) 30% de 50

50-------------------100%

x---------------------30%

100x = 50 . 30

100x = 1500

x = 1500÷100

x = 15

e) 40% de 90

90-------------------100%

x---------------------40%

100x = 90 . 40

100x = 3600

x = 3600÷100

x = 36