Equations:
m = k + 5
k = s + 2
m + k + s = 30
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Substitute for "m" and for "s"::
k+5 + k + k-2 = 30
3k +3 = 30
3k = 27
Kirsty has 9 marbles
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Mina has 9+5 = 14 marbles
Seb has 9-2 = 7 marbles
Hi!
A perfect square is the product of when a whole number is multiplied by itself
Ex:
6 × 6 = 36, 36 is the perfect square.
The number that is being multiplied is the square root.
So to find the correct answer for this question, let's use the process of elimination.
100 = 10 × 10 so we can cross out 100
64 = 8 × 8 so we can cross out 64
25 = 5 × 5 so we can cross out 25
Now all we have left is 24, which is not a perfect square.
Answer: A. 24
Hope this helps :)
Negative numbers aren't considered in any of those categories.
