Answer ONE of the following:
1. A student wanted to estimate 21.5 × 0.0079 by first rounding each number. He solved the problem as follows:
21.5 × 0.0079 is approximately equal to 20 × 0.008, which is equal to 0.016. So he estimated the answer as 0.016.
Do you agree with the answer? If not, explain where the student went wrong and give the correct answer.
2. In triangle A, the longest side is twice as long as the shortest side. In triangle B, the longest side is also twice as long as the shortest side. If this is the only information you have about the two triangles, can you conclude that they must be similar? Explain your answer.
3. The price of an item is reduced by 20% in a sale. Two weeks later the price is increased to 20% more than the sale price. Do you think that the item has been restored to its original price? If not, do you think its price is now higher or lower than the original price? Explain your thinking.
