Question

An ore contains 15% iron how much ore will be required to get 18kg iron

Answer 1

From the question, 
         100kg of an ore contains 15kg of iron.
Let mass required to obtain 18kg of iron be 'x'.
Then, 15/100 * x = 18kg  ⇒  x = 1800kg/15 = 120kg.
∴ Mass required to obtain 18kg of iron is '120kg'.
          

Answer 2

Answer:

100kg of an ore contains 15kg of iron.

Let mass required to obtain 18kg of iron be = x

Then, 15/100 * x =  18kg  ⇒  x =  1800kg / 15 = 120kg.

so the required amount would be 120 kg

Step-by-step explanation: