There are 27 purple marbles
Step-by-step explanation:
Let p be the purple marbles
and
w be the white marbles
Then according to given statements

Putting p = 4w-1 in equation 1

Adding one on both sides

Dividing both sides by 5

Putting w = 7 in equation 2

Hence,
There are 27 purple marbles
Keywords: Linear equation
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