The correct answer is A. 3 is in the ones place(3×1) 4 is in the tenths place(4×1/10) 0 is 0, and 5 is in the thousands place (5x1/1000)
Mary: x yrs old
Mike: 3x yrs old
In four yrs:
Mary: x+4 yrs old
Mike: 3x+4 yrs old
As the text of task:
3x+4=2(x+4)
3x+4=2x+8
3x-2x=8-4
x=4
Mary is 4 yrs old
All Ages:- 9, 13, 9, 10, 10, 9, 10, 10, 11, 9
No. of ages = 10
Mean = 
Mean of all Ages = 10 years
<h3>Hope This Helps</h3>
It would be 245r17 hope this helps
