Answer:
Below
Step-by-step explanation:
Difference= ‘-’
=

First order the numbers then cross out the numbers till in the middle the numbers 6.4 and 6.7 add then divide by two to get the middle and the median
13.1/2 =6.55
Answer:6.55
1.1
1.2
4.2
4.2
6.4
6.7
7.3
7.3
8
9.3
42.50$ ? 21 times 1.25 plus 13 times 1.25 = 42.50?