After one week a music downloading site sold over 80,000 songs. After 4 weeks the music downloading site sold over 300,000 songs. Find the average rate of change of songs per week.

75,000 songs per week

80,000 songs per week

55,000 songs per week

73,334 songs per week

Question

After one week a music downloading site sold over 80,000 songs. After 4 weeks the music downloading site sold over 300,000 songs. Find the average rate of change of songs per week.
		
75,000 songs per week
		
80,000 songs per week
		
55,000 songs per week
		
73,334 songs per week

misssunshinexxoxo · Answer

The rate changed by 220,000. Divide by 4 to get an average weekly rate.
220,000=55,000

anonymous · Answer

why wouldn't you divide by 3 instead of 4?

vocaloid · Answer

^ you would divide by 3, not 4, since the change takes place over three weeks

(300,000-80,000)/3 = 73,334 (rounded)

vocaloid · Answer

or, more generally:

rate of change = (number of CDs on week 4-number of CDS on week 1)/(4-1)

anonymous · Answer

ok thank you