To find 27x9 I find 27x10 and remove 1 group of 27

An appliance salesman sets a goal to sell an average of 6 appliances per day for the first two weeks of his new job. the dot plot shows the number he sold each day during the first 13 days. what is the minimum number of appliances he must sell on the 14th day in order to reach his goal? a) 5 b) 6 c) 7 d) 8

Need solving this second acceleration problem.

The reflexive property of congruence lets you say that ∠pqr ≅