Q105 · Practice questionSimple familiar1 mark
QUESTION 105
A census interval begins with 280 birds and ends with 310. During the interval there are 44 deaths, 12 immigrants and 18 emigrants. How many births occurred?
(A)
30
(B)
50
(C)
80
(D)
110
WORKED SOLUTION
1 markAnswer C
Answer
C
Working
The change is 30 = B − 44 + 12 − 18 = B − 50, giving B = 80 births. Deaths and emigrants must be replaced as well as the net population gain.
Marking criteria
- Select C. [1 mark]
Practice question aligned to the current QCAA syllabus; review the worked solution and marking criteria.
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