There are four pairs (m,n) that work: (5,10), (6,6), (8,4), and (12,3).
300 ordered
80% of them are hi-def
so 80% of 300
is 0.8 x 300 = 240
240 of the ordered TV's are hi-def
or if you used the images
each inteval is 30 (because 10% of anything is its self minus a 0)
count up 8 intervals and count up by 30s
you get 240
It's don't have equal between that equation ?
Answer:
total amount paid = 32.5 + 28.9 + 24.95 = 86.35
20% of the total amount paid = 0.2 * 86.35 = 17.27
you tip 17.25$
