A number when increased by 40%, gives 3920. The number is:

Correct option is D

Given:

A number when increased by 40% gives 3920. 

Solution:

​$$3920 = x \times (1 + \frac{40}{100}) \\\ \\3920 = x \times 1.40 \\\ \\x =\frac{ 3920 }{ 1.40} \\\ \\3920 = x \times 1.40 \\\ \\x = \frac{3920 }{ 1.40} = 2800$$​​

Thus, the number is 2800.