Number, NAPX-p169640v01

Question

A chemist makes 70 millilitres of a compound by mixing 20 millilitres of Chemical A and 50 millilitres of Chemical B.

If 250 millilitres of Chemical B is used to make a larger batch of the compound, how much Chemical A is needed?

Worked Solution

Chemical A : Chemical B = 20:5020:50 = 2 : 5

Let  x\ \large x = amount of Chemical A needed
x250\dfrac{\large x}{250} = 25\dfrac{2}{5}
x\large x = 2×2505\dfrac{2 \times 250}{5}
= {{{correctAnswer}}}

Variant 0

DifficultyLevel

566

Question

A chemist makes 70 millilitres of a compound by mixing 20 millilitres of Chemical A and 50 millilitres of Chemical B.

If 250 millilitres of Chemical B is used to make a larger batch of the compound, how much Chemical A is needed?

Worked Solution

Chemical A : Chemical B = 20:5020:50 = 2 : 5

Let  x\ \large x = amount of Chemical A needed
x250\dfrac{\large x}{250} = 25\dfrac{2}{5}
x\large x = 2×2505\dfrac{2 \times 250}{5}
= 100 mL

Question Type

Multiple Choice (One Answer)

Variables

Variable nameVariable value
correctAnswer
100 mL

Answers

Is Correct?Answer
x

200 mL

x

180 mL

x

120 mL

✓

100 mL

Tags