GMAT Question Bank IR

Hi Rich,

Though I understand the solution for the 2nd question, I do feel the expression of the definition - The size of each circle and the corresponding number in the circle indicate the proportion of Techtyx customer transactions in that region - quite confusing Could you help to explain it a bit?

When I first read it, I understood it as, let's say we have 5 different Appliance Companies (including Techtyx) selling appliances in A region and the total amount of customer transactions they do in such region sums up to 100,000$, so the amount of Techtyx customer transactions in that region will equal to 0.29 * 100,000$ = 29,000$.

I know that if understanding it in such way, we can not find out the answer, but how can I understand the intended meaning exactly in the first place I mean, is it because this expression actually could be interpreted in such two ways, or because I am wrong here? And if so, what the definition will be to express the meaning above?

Thanks for your response

What we see: a Graphics Interpretation question. One bubble chart packs three facts about each of Techtyx's six regions: how far right the bubble sits is last year's sales, how high it sits is the number of product types, and its size and label are that region's share of all customer transactions.

Step 1. Read each bubble's three numbers.
What we see: reading the centers off the axes, roughly:
A: sales 500, products 10, share 0.29
B: sales 250, products 20, share 0.08
C: sales 820, products 33, share 0.33
D: sales 550, products 39, share 0.10
E: sales 700, products 42, share 0.05
F: sales 900, products 46, share 0.15
What it means: sales are in thousands of euros, and the share tells us how many of the company's transactions happened in that region.
What we do and why: write these down once. Both blanks come from this list, and rough readings are enough because the gaps are large.

Step 2. Blank a: the region with the most transactions, ranked by product types.
What we see: the biggest share is C at 0.33.
What it means: now rank all six by height, most product types first: F (46), E (42), D (39), C (33), B (20), A (10).
What we do and why: C lands fourth. The size of C's bubble pulls the eye, but the question asks about its height, and three smaller bubbles sit above it.

Step 3. Blank b: the region with the largest average transaction.
What we see: average transaction = sales in the region divided by the number of transactions in the region.
What it means: we do not know the company's total number of transactions, but every region uses the same total, so dividing sales by the share ranks the regions correctly. Pretend there were 100 transactions in all:
A: \(500 \div 29 \approx 17\)
C: \(820 \div 33 \approx 25\)
E: \(700 \div 5 = 140\)
F: \(900 \div 15 = 60\)
What we do and why: E wins by far. It has solid sales spread over very few transactions, so each one is large.

The trap: for blank b, picking F or C because they have the most sales. Big sales spread over many transactions make a small average. The average depends on sales and how many transactions share them.
Faster way: for blank b, look for a bubble that sits far right but is tiny. Far right means big sales, tiny means few transactions. E is the only one like that.
Takeaway: average per item = total divided by count. When a chart gives only shares, divide by the shares; the unknown total cancels out when you compare.

Answer: fourth, E