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valentina_108 [34]

3 years ago

6

Em uma enorme ampulheta, foram colocadas 40 kg de areia. Sabe-se que a areia escoa lenta e uniformemente à razão de 500g por dia

e que 2/5 da areia inicial já escoaram. Quantos dias faltam para a areia escoar totalmente?

1 answer:

puteri [66]3 years ago

6 0

Answer:

48 dias

Step-by-step explanation:

1000 gramas = 1 kg

A quantidade inicial de areia = 40kg

1 kg = 1000g

40kg = x

Multiplicação cruzada

1 kg × x = 40 kg × 1000g

x = 40 kg × 1000g / 1 kg.

x = 40,000 gramas

Somos informados de que 2/5 se esgotou.

Quantidade que foi drenada =

40,000 × 2/5

= 16,000 gramas foram drenados

Quantidade restante = 40,000 gramas - 16,000 gramas

= 24,000 gramas

A areia escoa a 500g por dia, portanto,

500g = 1 dia

24,000g = x

Multiplicação cruzada

500g × x = 24, 000 × 1

x = 24,000 g × 1 dia / 500

x = 48 dias

Restariam 48 dias para que a areia restante vazasse.

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