Henry Park Pri Sch 2007 PSLE Math Prelim Q42

At first, the total number of sheep in Farm A and Farm B was 980. After 3/5 of the sheep in Farm A and 200 of the sheep in Farm B are sold, the ratio of the number of sheep in Farm A to Farm B becomes 1 : 4.
a) Find the number of sheep in Farm B at first.
b) Find the total number of sheep left in Farm A and Farm B.

Solution


13 units ----- 980 – 200 = 780
1 unit ----- 780 divided by 13 = 60
a) Number of sheep in Farm B at first -----
8 units + 200 ----- (8 x 60) + 200 = 680

Answer: There were 680 sheep in Farm B at first.

b) Total number of sheep left in Farm A and Farm B -----
10 units ----- 10 x 60 = 600

Answer: There were 600 sheep left in both farms.