The average of five weights is 13 grams. this set of of five weights is then increased by another weight of 7 grams. what is the average of the 6 weights?

12 g

Step-by-step explanation:

Recall that

Average Weight = Sum of All weights  ÷ Number of Weights

in the first case we are given that average of 5 weights is 13g

i.e Average weight (of 5 weights) = 13g and number of weights = 5

or, using the formula above,

13 = sum of 5 weights ÷ 5   (rearranging)

sum of 5 weights = 13 x 5 = 65 g

we are subsequently told that one more weight of 7 g is added,

hence, new number of weights = 6

and,

sum of 6 weights = sum of original 5 weights + sum of 6th weight

= 65 g + 7 g = 72 g

once again using the first formula

Average Weight (of 6 weights) = Sum of All weights  ÷ Number of Weights

= 72  ÷ 6

= 12g

180

step-by-step explanation: