ravi gave 60% of his stamp collection to his brother. He sold 20% of the remaining amount. what percent of his collection did he sell?

Ineed to know the answer to this algebra question.

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Apolice office claims that the proportion of people wearing seat belts is less than 65%. to test this claim, a random sample of 200 drivers is taken and its determined that 126 people are wearing seat belts. the following is the setup for this hypothesis test: h0: p=0.65 ha: p< 0.65 find the p-value for this hypothesis test for a proportion and round your answer to 3 decimal places.