GMAT Integrated Reasoning

On days 1 through 4 of a recent week, product X was out of stock at Retailer R. Day 1 shoppers are those who came to Retailer R on day 1 of that week seeking Product X. for each of the first 3 days of that week, the graph shows the subsequent behavior of all the day 1 shoppers who came to Retailer R seeking Product X on that day. Shoppers at Retailer R who purchased a different item in lieu of Product X paid an average of 30% more for the item.

From each drop-down menu, select the option that creates the most accurate statement based on the information provided.

Any 1?

For the first question, we're trying to determine what % of the shoppers from the first day, returned on the third. Well, we know from the bar graph that only 25% of the shoppers returned on Day 2, and 75% didn't come back at all that week.

Of the 25% who returned on Day 2, 19% came back on Day 3. So the percent who showed up on Day 1 and returned on Day 3 would be 19% of the 25% who returned on Day 2, or (.19)(.25.) Let's round that 19% up to 20% and find (.20)(.25) = .05, or about 5%. (I can't access the pulldown bar, so I don't know how the answer is depicted, but whatever it is, it should be close to 5%.)

For the second question, let's say there were 10 shoppers there on Day 1. We'll say that the item in question costs $1, so if all 10 bought the item, they'd have paid a total of $10.

We know that 60% purchased a separate item, so 6 of the 10 purchased a substitute item. We also know that those who purchased a different item paid 30% more, so rather than $1, they'd have paid $1.30. If 6 people paid $1.30 each, they'd have spent a total of 6*1.30 = 7.80.

So (total amount spent on substitute items)/(total amount that would have been spent with no sub) = 7.80/10 = 78%.

Thanks David. It was helpful.