The doctor recommended that Matt decrease the number of calories he consumed from 3,000 to 2,400. By what percent did the number of calories decrease?

28%

Step-by-step explanation:

28%

Step-by-step explanation:

1800/2500 = 0.72

0.72 = 72%

100% - 72% =  28%

answer: first option i.e. 'a' is correct.

step-by-step explanation:

since we have given that

number of minutes to wrap a small gift box = 4 minutes

we need to find the number of gifts to be wrapped in 5 minutes

since there is a direct variation, as the number of minutes will increase with   number of gifts to be wrapped.

so, let the number of gifts to be wrapped in 5 minutes be x.

so, it becomes,

hence, first option 'a'   is correct.