Answer: {4, 14, 24, 34, 44}
Explanation:
A general number can be written as:
aₙ*10ⁿ + ... + a₂*10² + a₁*10¹ + a₀*10⁰ + a₋₁*10⁻¹ ...
Where the a₁ coefficient is the "unit" of a number.
For example, the number 145.2 can be written in this form as:
1*10² + 4*10¹ + 5*10⁰ + 2*10⁻¹
Then the numbers having a 4 in the unit place, will be the numbers that have the digit 4 just at the left of the decimal point.
the set of natural numbers having 4 in the unit place, that also are between 1 and 50 are:
{4, 14, 24, 34, 44}