Number of different regions = 113
Average of stores per region = 181
Average units sold per store = 51752
Total number of units of manufacturer’s product sold worldwide last year = 113 * 181 * 51752
We should use estimation here
110 * 180 * 50,000
= 198 * 10^2 * 50,000
= 2 * 10^4 * 5* 10^4
= 10 * 10^8
=10^9
Answer D
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Total Number of Stores = 181 * 113

Total Number of Products sold = 181 * 113 * 51752

= 1.81 * 10^2 * 1.13 * 10^2 * 5.1752 * 10^4
=1.8*1.1*5.17 * 10^8

Approx = 2*1*5 * 10^8 = 10*10^8= 10^9

We are given that a certain manufacturer sells its products to stores in 113 different regions, with an average (arithmetic mean) of 181 stores per region and 51,752 units per store.

Since we are asked, which of the following is closest to the total number of units of manufacturer’s product sold worldwide last year, we can use estimation.

113 ≈ 100

181 ≈ 200

51,752 ≈ 50,000

Thus, the approximate number of units sold worldwide last year was:
100 x 200 x 50,000 = 1,000,000,000 = 10^9

Answer: D
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1. 181 Stores x 113 regions = 20,453
2. 20,453 x 51,752 (I worked this out the long way but scientific notation is faster)
3. 2 x 10^4 x 5 x 10^4 = 10 x 10^8 (just add exponents since base and exponent is the same)
4. 10^9

Answer (D)