Answer:
% Decrease = 19.2 ; 19.2%
Step-by-step explanation:
% Decrease = (Original Price - New price)/ Original price × 100
% Decrease = (78 - 63)/78 × 100
% Decrease = 15/78 × 100
% Decrease = 19.23
21 its 21 because it is 21
A proportional relationship is used to illustrate linear equations.
The constant of proportionality is 3
From the table, we have the following points:
(x,y) = (2,6) (3,9)
The constant of proportionality is calculated using:

So, we have:

Subtract

Divide

Hence, the constant of proportionality is 3
Read more about constants of proportionality at:
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