Mark ( ) against the correct answer in the following: An ore cont… - Vidyadip

MCQ

Mark $(\checkmark)$ against the correct answer in the following:
An ore contains $5\%$ copper. How much ore is required to obtain $400g$ of copper:

A
$2kg$
B
$4kg$
C
$6kg$
✓
$8kg$

✓

Answer

Correct option: D.

$8kg$

Let $x$ $kg$ be the required amount of ore.
$=\frac{\text{x}\times5}{100}=400$
$\text{x}=\frac{400\times100}{5}=8000\text{g}$
$=8\text{kg}$

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