PSLE Ivory and Seth bought durians at the prices shown below.
3 Large durians for $7
5 Small durians for $4
- Ivory bought an equal number of large and small durians. She spent $92 more on the large ones. How many durians did she buy altogether?
- Seth spent an equal amount of money on the large and small durians. What fraction of the durians he bought were large?
(a)
Number of large and small durians that Ivory bought is the same. Make the number of large and small durians the same. LCM of 3 and 5 is 15.
Cost of 3 large durians = $7
Cost of 15 large durians = 5 x 7 = $35
Cost of 5 small durians = $4
Cost of 15 small durians = 3 x 4 = $12
Difference in the cost of buying 15 small durians and 15 large durians
= 35 - 12
= $23
Number of sets of durians
= 92 ÷ 23
= 4
Number of durians that Ivory bought
= 4 x 2 x 15
= 120
(b)
Seth spent an equal amount of money on the large and small durians. Make the amount of money spent on the large and small durians the same.
LCM of 7 and 4 is 28.
Number of large durians that Seth bought
= 3 x (28 ÷ 7)
= 3 x 4
= 12
Number of the small durians that Seth bought
= 5 x (28 ÷ 4)
= 5 x 7
= 35
Fraction of the durians that Seth bought that were large
=
1212 + 35 =
1247 Answer(s): (a) 120; (b)
1247