Let E be the set of integers whose unit digit is 1. If a number is chosen uniformly from {2, 3, 4, …, 50}, what is the probability that it belongs to E?

Introduction / Context:We count how many integers between 2 and 50 inclusive end with digit 1. Divide by the total count to obtain the probability.

Given Data / Assumptions:

• Range: {2,3,…,50} has 49 numbers.
• Numbers with unit digit 1 in this range: 11, 21, 31, 41.

Concept / Approach:Simple counting; all outcomes equally likely.

Step-by-Step Solution:

Verification / Alternative check:Note that 1 and 51 lie just outside the range; hence there are exactly four valid entries spaced by 10.

Why Other Options Are Wrong:5/49, 3/49, 2/49 are inconsistent with the explicit list.

Common Pitfalls:Accidentally including 1 or 51, which are not in the specified set.

Final Answer:4/49