Here’s and example of a **SMART MATH** problem for **AVERAGES.**

**Problem**

**Problem**

The average weight of a sac of wheat in a truck is reduced by 0.2 lbs from 50 lbs when 5 new sacs, each weighing 47.4 lbs on an average, are loaded. How many sacs did the truck originally carried?

- 60
- 62
- 64
- 66
- 68

**The Usual Method**

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Let there be ‘*x*’ number of sacs in the truck originally.

Hence total weight of the load in the truck = 50*x*

New number of sacs = *x* + 5

New average weight = = (49.8*x* + 249) lbs

Total weight of new sacs = 47.4 x 5 = 237 lbs

Hence 49.8*x* + 249 = 50*x* + 237

**(Ans: 1)**

*Estimated Time to arrive at the answer = 60 seconds.*

**Using Technique**

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Difference between the average weight of the original sacs and the new sacs = 50 – 47.4 = 2.6lbs

Total difference = 2.6 x 5 = 13 lbs. Now this 13 lbs is reduced from the total weight of (*x* + 5) bags and the reduction is that of 0.2 lb each. Hence

lbs

**(Ans: 1)**

*Estimated Time to arrive at the answer = 15 seconds.*

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