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Wednesday, April 14, 2010

CHIJ St Nicholas Girls' Sch 2009 P6 SA1 Paper 2 Q14

There were ducks, goats and hens at a farm. 15% of the animals were ducks. There were 180 fewer ducks than hens. The remaining 121 animals were goats. What percentage of the animals at the farm were goats? Levae your answer correct to 2 decimal places.

Solution


* 180 more hens than ducks, therefore hens --> 15% + 180.
** Ducks (15%) and hens (15% + 180), therefore goats give the remaining 70% less 180.

70% - 180 --> 121
70% --> 121 + 180 = 301
10% --> 301 divided by 7 = 43
100% 10 x 43 = 430

Percentage of animals were goats
--> (121/430) x 100% = 28.139% ~ 28.14%

Answer: 28.14%

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