The equation that represents the number of T-shirt , number of colours of shirt and total order is 3x + 50xy.
The number of colours and T- shirts are the variable quantity while the cost of order is the fixed quantity.
The number of members in the school choir = 75
The charge for one shirt = $3
Let the number of T-shirts ordered be x
Cost of ordering x shirts = 3x
Therefore,
Charge for each colour to be printed = $50
Let the number of colours to be printed on each T- shirt be represented by y
Therefore,
Cost of printing y colours on each T- shirt = 50y
Cost of printing y colours on x number of T-shirts = x(50y) = 50xy
Hence, the equation that represents the number of T-shirt , number of colours of shirt and total order is as follows:
Total cost = 3x + 50xy
Hence, the fixed quantity and variable quantity are as follows:
The number of colours on the shirts is a variable quantity
The number of shirts ordered is a variable quantity
The cost of order is fixed quantity
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