David's freight forwarding company charges $15 for every vase delivered on time and $10 for every vase delivered late. In the month of September, David's freight forwarding company collected $2430. For every 19 vases delivered, 16 were delivered on time and 3 were delivered late.

1. What was the total number of vases delivered on time?
2. How much less money did David's freight forwarding company collect in September due to the late deliveries of the vases?

	On time	Late	Total
Number	16 u	3 u
Value	15	10
Total Value	240 u	30 u	270 u

(a)
Total amount collected in September
= 240 u + 30 u
= 270 u

270 u = 2430

1 u = 2430 ÷ 270 = 9

Total number of vases delivered on time
= 16 u
= 16 x 9
= 144

(b)
Amount that David's freight forwarding company collected less from each late delivery of vases
= 15 - 10
= $5

Number of vases delivered late
= 3 u 
= 3 x 9
= 27

Amount that David's freight forwarding company collected less from all the late deliveries of vases 
= 27 x 5
= $135

Answer(s): (a) 144; (b) $135