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Re: Mrs. William invited 120 guests who were either her relatives or her c
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10 Apr 2023, 09:53
Let's denote the number of Mrs. William's relatives as "R" and the number of her colleagues as "C".
From the given information, we know that 60% of the total guests were Mrs. William's colleagues. This can be expressed as:
0.60 * 120 = 72
So, there were 72 guests who were her colleagues.
We also know that 20% of her relatives were also her colleagues, which can be expressed as:
0.20 * R
Since these two groups overlap (some guests may be both relatives and colleagues), we need to subtract the overlapping portion to avoid double counting. Therefore, we can write the total number of guests as:
R + C - 0.20R
We are told that the total number of guests is 120, so we can set up an equation:
R + 72 - 0.20R = 120
Simplifying, we get:
0.80R = 48
Dividing both sides by 0.80, we get:
R = 60
So, there were 60 guests who were Mrs. William's relatives. Therefore, the correct answer is 60.