For the school play, most of the chairs are in rows of 10 each, with one row of 8 chairs. If there are 78 chairs altogether, how many rows are there?
well, 78-8 = 70
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To find the number of rows, we will first determine the number of chairs in each row and then divide the total number of chairs by that amount.
In this case, most of the chairs are in rows of 10 each. We also have one row with 8 chairs. So the majority of rows will have 10 chairs and one row will have 8 chairs.
To calculate the number of chairs in the majority of rows, we multiply the number of rows by the number of chairs in each row. Let's call the number of rows with 10 chairs "x."
The number of chairs in the majority of rows = x * 10
The number of chairs in the row with 8 chairs = 8
Since we have a total of 78 chairs, we can equate this information in an equation:
x * 10 + 8 = 78
To solve for x, we subtract 8 from both sides of the equation:
x * 10 = 78 - 8
x * 10 = 70
Now, to find the value of x, we divide both sides of the equation by 10:
x = 70 / 10
x = 7
Therefore, there are 7 rows in total.