Question

Jasmine has a bag of sweets. It has 3 yellow sweets, 5 green sweets, 7 red sweets, 4 purple sweets and 1 black sweet. If Jasmine takes out one sweet whose probability is $\frac{1}{4}$, then what colour sweet has she taken out ?

• A. Green
• B. Yellow
• C. Red
• D. Purple

Answer 1

The correct option is A Green

Let $x$ be the number of that coloured sweet which has a probability of $\frac{1}{4}$.

Total number of sweets = 20

$\text{Probability of taking out a particular coloured sweet}=\frac{\text{Numbet of sweets of that colour}}{\text{Total number of sweets}}\Rightarrow \frac{1}{4}=\frac{x}{20}$
$\Rightarrow x=5$
So, desired colour of the sweet is Green.

[Alternatively,
Number of yellow sweets = 3
Number of green sweets = 5
Number of red sweets = 7
Number of purple sweets = 4
Number of black sweets = 1
Total number of sweets = 20
$\text{Probability of taking out a yellow sweet}=\frac{\text{Number of yellow sweets}}{\text{Total number of sweets}}=\frac{7}{20}$
Similarly,
$\text{Probability of taking out a green sweet}=\frac{5}{20}=\frac{1}{4}$
This can be calculated for the other colored sweets as well. We will see that if Jasmine takes out one sweet whose probability is $\frac{1}{4}$, then it should be green coloured sweet only.]