Answer:
Alexander sold
8 tickets on Tuesday
16 tickets on Wednesday
7 tickets on Thursday
Explanation:
Let us represent:
Number of tickets sold on Tuesday = a
Number of tickets sold on Wednesday = b
Number of tickets sold on Thursday = c
In three days Alexandra sold a total of 31 tickets to her school play.
a + b + c = 31...... Equation 1
On Tuesday she sold as twice as many tickets as on Wednesday.
2a = b
And on Thursday, she sold exactly seven tickets.
c = 7
Substitute 2a for b and 7 for c in Equation 1
a + b + c = 31...... Equation 1
a + 2a + 7 = 31
3a = 31 - 7
3a = 24
a = 24/3
a = 8 tickets
Note that
2a = b
a = 8 tickets
2 × 8 = 16 tickets
b = 16 tickets
Therefore, Alexander sold
8 tickets on Tuesday
16 tickets on Wednesday
7 tickets on Thursday