Simplification and Approximation Questions

Multiple choice
  1. 240

  2. 151

  3. 218

  4. 122

  5. 162

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

We need to calculate 45% × 299.99 + √399.99 × 4/5. Approximating: 45% × 300 = 135 (since 45% = 0.45, and 0.45 × 300 = 135). √400 = 20. 20 × 4/5 = 20 × 0.8 = 16. Total = 135 + 16 = 151. This matches option B. The question asks for approximate value, so using 300 instead of 299.99 and 400 instead of 399.99 is the correct approach.

Multiple choice
  1. $-167$
  2. $-179$
  3. $-209$
  4. $-245$
  5. $-130$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

We need to find ? in (215.98)^(1/3) × √120.6 - ? = 35% × 698. Rearranging: ? = (215.98)^(1/3) × √120.6 - 35% × 698. Approximating: ³√216 = 6 (since 6³ = 216). √121 = 11 (since 11² = 121). 35% × 700 = 0.35 × 700 = 245. So ? ≈ 6 × 11 - 245 = 66 - 245 = -179. This matches option B. The calculation is straightforward with proper approximations.

Multiple choice
  1. 28

  2. 17

  3. 35

  4. 24

  5. none of these इनमें से कोई नहीं

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Approximate: 29.98% of 779.95 ≈ 30% of 780 = 0.30 × 780 = 234. And 25.05% of 219.97 ≈ 25% of 220 = 0.25 × 220 = 55. Sum = 234 + 55 = 289. Now √289 ≈ 17 (since 17² = 289). The answer is approximately 17.

Multiple choice
  1. $\(\frac{12}{25}\)$
  2. $\(\frac{144}{25}\)$
  3. $\(\frac{13}{3}\)$
  4. $\(\frac{5}{71}\)$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

6.25% of 25 = 1.5625, 25% of 50 = 12.5, 14% of 25 = 3.5. So 1.5625 + 12.5 - 3.5 = 10.5625. √10.5625 = 3.25 = 13/4. Wait, let me recalculate: 6.25% = 1/16, so (1/16) × 25 = 25/16. 25% × 50 = 12.5 = 25/2. 14% × 25 = 3.5 = 7/2. Expression = 25/16 + 25/2 - 7/2 = 25/16 + 18/2 = 25/16 + 9 = 169/16. √(169/16) = 13/4. But 13/3 = 4.33, 13/4 = 3.25. Let me verify: 169/16 = 10.5625, √10.5625 = 3.25 = 13/4. Option C is 13/3, not 13/4. There's a discrepancy. Actually, let me check the expression again: 25/16 + 25/2 - 7/2 = 25/16 + (25-7)/2 = 25/16 + 18/2 = 25/16 + 9 = 25/16 + 144/16 = 169/16. √(169/16) = 13/4. This doesn't match 13/3. However, the question asks for √(6.25% of 25 + 25% of 50 - 14% of 25). Let me recalculate: 6.25% = 0.0625 = 1/16, 0.0625 × 25 = 1.5625. 0.25 × 50 = 12.5. 0.14 × 25 = 3.5. Sum: 1.5625 + 12.5 - 3.5 = 10.5625. √10.5625 = 3.25 = 13/4. The answer should be 13/4, not 13/3. But given the options, 13/3 is marked correct. There might be an error in the question or my calculation.

Multiple choice
  1. 662

  2. 504

  3. 548

  4. 448

  5. 580

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Calculate: (250.87 × 8.12 × 6.829) ÷ 25 = ? × 11.86. Approximation: (251 × 8.1 × 6.8) ÷ 25 ≈ 251 × 8.1 × 0.272 ≈ 251 × 2.2 ≈ 552. Then 552 - 11.86 ≈ 540. Option C (548) is closest. Precise calculation: 250.87 × 8.12 = 2037.0664, then × 6.829 = 13911.47, then ÷ 25 = 556.46. Then 556.46 - 11.86 = 544.6. Option C (548) is closest.

Multiple choice
  1. $180$
  2. $220$
  3. $130$
  4. $240$
  5. $165$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Approximating: (10.998)² ≈ 11² = 121, (16.221)² ≈ 16² = 256, (14.441)² ≈ 14² = 196. So 121 + 256 - 196 = 181. The closest approximation is 180. This tests ability to round decimals to nearest integers and compute quickly.