Step 1: Arrange the numbers from least to greatest.

GIVEN: 13, 6, 10, r

r = ?

Mode = 13

Least to greatest.

6, 10, 13, (r =?)

Step 2: Find the missing number

NOTE: The mode is the number that appears most often.

From the definition

6 - 1 time

10 - 1 time

13 - 1 time

This all numbers are repeating only one time. so we can find the mode based

on the r value.

If r = 13

6, 10, 13, 13

The number that appears most often is 13. When r = 13, the mode is 13.

( If you take r = 6 or 10, then 6 or 10 will become mode. but in the question

they given the mode as 13, So I took r = 13)