7 rolls of blue tickets were ordered by the student council.
An equation is an expression that shows the relationship between two or more numbers and variables.
Let x represent the number of blue tickets. 1550 tickets were ordered of which 150 were golden, hence:
x = 1550 - 150
x = 1400
Since each blue ticket is in roll of 200, hence:
Number of roll = 1400 / 200 = 7
7 rolls of blue tickets were ordered by the student council.
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