If a number between 0 and 1 is selected at random, which of

the answer should be E, since the larger range the larger probability of choosing a number from that range

Good question.

Deduct the fractions from each other to determine the largest gap and thus largest range.

Nice concept is used . the number is most likely to be available in the largest range

Since this a probability question, it would be a smart way to look at the fractions given in the options in terms of percentages. For example, the fraction \(\frac{3}{20}\) given in option A represents 15%. Therefore, when we pick a number from 0 and 1, the probability that it is between 0 and 0.15 is fairly low.

Going by this approach, we can work out the percentages related to the fractions given in every option.
Option B – \(\frac{3}{20}\) and \(\frac{1}{5}\) – 15% and 20% which is 5%
Option C – \(\frac{1}{5}\) and ¼ - 20% and 25% which is 5% as well
Option D – ¼ and \(\frac{3}{10}\) – 25% and 30% which is again 5%
Option E – \(\frac{3}{10}\) and ½ - 30% and 50% and we have the largest interval of 20%

Clearly, the biggest interval is the one given in option E. So, if we pick a number between 0 to 1, we can say that the interval given in option E has the highest probability (of the given options) that the number we picked lies in this interval.

The correct answer option, therefore, is E.

Hope that helps!

make all the base same, in this case 100.

the largest range is between 3/10 and 1/2 making its probability highest.

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