Question 1207263
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Answer:  <font color=red>72</font>


Work Shown


2/5 of the batch is rotten, so the remaining 3/5 of the batch is still good. 
The two fractions add to 5/5 aka 1. Draw a fraction diagram if needed. 


3/5 of 80 = (3/5)*80 = 48 kg of durians are still good.


n = number of packets
(2/3)n = total weight since each packet weighs 2/3 kg
(2/3)n = 48
2n = 3*48
n = 3*48/2
n = <font color=red>72</font> is the answer we want.
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