Question
Aluminium is extracted from aluminium oxide. (b) 38% of a rock sample is aluminium oxide. rock sample __ __ Mass of aluminium oxide =underline ( )kg (2)
Answer
3.6
(245 Votes)
Ivan
Elite · Tutor for 8 years
Answer
15.2kg
Explanation
To calculate the mass of aluminium oxide in the rock sample, we basically need to find 38% of 40 kg. This process is relatively simple and requires merely basic arithmetic skills. We're given that 38% of the total mass of the rock is constituted by Aluminium oxide. Therefore, we need to find wha number 38% of 40 is, because the total mass of the rock is said to be 40kg. Using the formula for percentage calculations ie, (percentage/100) * Total = answer.Iterator through the problem like this, we find that the mass of aluminium oxide in a 40 kg rock sample is 38/100 * 40 kg. Calculating and rounding up to two decimal places, if needed.