<span>Let the original number of seats in a row be x;
</span>Let the number rows be y;
( x + 3) * (y - 2 )= 72 and x * y = 72 => 72 + 3 * y - 2 * x = 72 => 3 * y = 2 * x;
=> x is divisible by 3;
1. x = 3 => y = 72 / 3 => y = 24;
2. x = 6 => y = 72 / 6 => y = 12;
3. x = 9 => y = 72 / 9 => y = 8;
4. x = 12 => y = 72 / 12 =. y = 6;
5. x = 24 =. y = 72 / 24 => y = 3;
6. x = 36 => y = 72 / 36 => y = 2;
7. x = 72 => y = 72 / 72 => y = 1;
My analysis tell me that the right answer is 9 seats in a row and 8 rows;
The original number in each row is 9.
B=number of ticets sold before
a=number of tickets sold after
cost of a ticket=number of tickets times cost per ticket
beforecost=39.95b
aftercost=54.95a
total cost=925000
39.95b+54.95a=925000
total number tickets=20000
b+a=20000
we have
39.95b+54.95a=925000
b+a=20000
multiply second equation by -39.95 and add to first equatin
39.95b+54.95a=925000
<u>-39.95b-39.95a=-799000 +</u>
0b+15a=126000
15a=126000
divide bot sides by 15
a=8400
sub back
b+a=20000
b+8400=20000
minus 8400 both sides
b=11600
11,600 tickets sold before
8400 tickets sold after
X 3x+7 y (x, y)
1 3(1) +7 10 (1,10)
2 3(2) +7 13 (2,13)
3 3(3) +7 16 (3,16)
4 3(4) +7 19 (4,19)
8 > 7 +
Subtract 7 from both sides
1 >
Multiply both sides by 6
6 > x Flip it around so it's easier to read
x < 6
You can graph your answer by drawing an open circle at the 6 and coloring the line to the left. The circle should be open, because x is <em>less than 6</em>, not less than or equal to. You would color to the left to show that x can be anything less than 6.
Answer:
To be precise, I think it's a pattern question, where you have to add 4 to each number. I'm not very sure though.