Small durians	Medium durians	Large durians
$4	$6	$7

Oscar had some durians in 3 sizes. The number of medium durians was five times the number of large durians. The number of large durians were thrice the number of small durians. He sold all the small and medium durians. He received $56 from selling ²₃ of the large durians.Oscar had some durians in 3 sizes. 
He sold all the small and medium durians. He received $56 from selling ²₃ of the large durians.

1. How many medium durians did he have at first?
2. How much more did he collect from selling the medium durians than the small durians?

Small durians	Medium durians	Large durians
	5x3	1x3
1x1		3x1
1 u	15 u	3 u

(a)
The number of large durians is the repeated identity. Make the number of large durians the same.  LCM of 1 and 3 is 3.

	Small durians	Medium durians	Large durians
Before	1 u	15 u	3 u
Change	- 1 u	- 15 u	- 2 u
After	0	0	1 u

Number of large durians that Oscar sold
= ²₃ x 3 u
= 2 u

	Small durians	Medium durians	Large durians
Number	1 u	15 u	2 u
Value	$4	$6	$7
Total value	4 u	90 u	14 u

Amount that Oscar received from selling of ²₃ of the large durians = 14 u
14 u = 56

1 u = 56 ÷ 14 = 4

Number of medium durians at first
= 15 u
= 15 x 4
= 60

(b)
Amount that Oscar collected more from selling the medium durians than the small durians
= 90 u - 4 u
= 86 u
= 86 x 4
= $344

Answer(s): (a) 60; (b) $344