Approximate the value of 74.99% of 1299 plus 8.98% of 1899. (Round your answer to the nearest whole number.)

Difficulty: Medium

Correct Answer: 1,145

Explanation:


Introduction / Context:
This question tests the ability to handle percentages with non-integer values and perform approximate calculations accurately. It is a common type of problem in banking, finance and competitive exams, where values like 74.99% and 8.98% appear to reflect near rounded percentages. The focus is on systematic computation and correct rounding rather than mental shortcuts alone.


Given Data / Assumptions:

    We need to compute 74.99% of 1299.
    We also need to compute 8.98% of 1899.
    Then we add both results and round to the nearest whole number.
    All percentages are treated as exact decimal values and calculations use standard arithmetic.


Concept / Approach:
First, convert each percentage into its decimal form by dividing by 100. Then multiply each decimal by its corresponding number. After obtaining the two products, add them together to get the combined value. Finally, round the result to the nearest integer. Using approximate mental checks is helpful, but a structured calculation ensures accuracy.


Step-by-Step Solution:
Step 1: Convert 74.99% to decimal form. 74.99% = 74.99 / 100 = 0.7499. Step 2: Compute 0.7499 * 1299. 0.7499 * 1299 is approximately 974.18 (keeping a few decimal places). Step 3: Convert 8.98% to decimal form. 8.98% = 8.98 / 100 = 0.0898. Step 4: Compute 0.0898 * 1899. 0.0898 * 1899 is approximately 170.47. Step 5: Add both partial results. Combined value ≈ 974.18 + 170.47 = 1,144.65. Step 6: Round 1,144.65 to the nearest whole number. This rounds to 1,145. So the required approximate value is 1,145.


Verification / Alternative check:
As a rough mental check, we can approximate 74.99% as 75% and 8.98% as 9%. Then 75% of 1300 is about 975, and 9% of 1900 is about 171. Adding 975 and 171 gives 1,146. This quick estimate is very close to the more accurate calculated value of about 1,145, which supports the correctness of our more precise computation.


Why Other Options Are Wrong:
1,120 and 1,100 are too small compared to both the precise and rough calculations, implying a significant underestimation of the percentages.
1,190 and 1,210 are too large and would require much higher effective percentages than those given.
Among the options, only 1,145 properly matches the accurate and approximate computations.


Common Pitfalls:
A common mistake is to round the percentages to 75% and 9% at the very beginning and then round again at intermediate steps, which can introduce larger errors. Another issue is misplacing the decimal when converting from percentage to decimal, for example writing 0.7499 as 7.499. Learners may also incorrectly add the percentages directly to the numbers instead of multiplying. Always remember to convert percentages to decimals, multiply by the base number, and then add the results.


Final Answer:
The approximate value of the expression is 1,145 (to the nearest whole number).

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