PSLE Ivory and Oliver bought durians at the prices shown below.
3 Large durians for $15
4 Small durians for $9
- Ivory bought an equal number of large and small durians. She spent $99 more on the large ones. How many durians did she buy altogether?
- Oliver spent an equal amount of money on the large and small durians. What fraction of the durians he bought were small?
(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 4 is 12.
Cost of 3 large durians = $15
Cost of 12 large durians = 4 x 15 = $60
Cost of 4 small durians = $9
Cost of 12 small durians = 3 x 9 = $27
Difference in the cost of buying 12 small durians and 12 large durians
= 60 - 27
= $33
Number of sets of durians
= 99 ÷ 33
= 3
Number of durians that Ivory bought
= 3 x 2 x 12
= 72
(b)
Oliver 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 15 and 9 is 45.
Number of large durians that Oliver bought
= 3 x (45 ÷ 15)
= 3 x 3
= 9
Number of the small durians that Oliver bought
= 4 x (45 ÷ 9)
= 4 x 5
= 20
Fraction of the durians that Oliver bought that were small
=
209 + 20 =
2029 Answer(s): (a) 72; (b)
2029