An expression which gives the number of cookies that Priti still has at the end of third period is 2C/5.
<h3>How to determine the
expression?</h3>
For the first period, we have:
First period = 1/4 × C
First period = C/4.
Remaining = C - C/4 = 3C/4
For the second period, we have:
Second period = 1/5 × 3C/4
Second period = 3C/20.
Remaining = 3C/4 - 3C/20 = 12C/20
For the third period, we have:
Third period = 2/3 × 12C/20
Third period = 24C/60.
Third period = 2C/5.
Read more on expressions here: brainly.com/question/12189823
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