Simplification and Approximation Questions

Multiple choice
  1. 210

  2. 220

  3. 190

  4. 195

  5. 200

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

298.98 ≈ 299. 16.01² = 256.08 ≈ 256. Sum = 299 + 256 = 555. 12.01² ≈ 144. 12% of 555 = 0.12 × 555 = 66.6. Adding 144: 66.6 + 144 = 210.6 ≈ 210. The answer 210 matches option A.

Multiple choice
  1. 365

  2. 340

  3. 356

  4. 345

  5. 375

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

Approximating using roots: (99867)^(1/2) = √99867 ≈ 316, (65547)^(1/4) = √(√65547) ≈ √256 = 16, (19712)^(1/3) = ∛19712 ≈ 27, (1314)^(1/4) = √(√1314) ≈ √36 = 6. LHS = 316 + 16 + 27 + 6 = 365. RHS = (6571)^(1/4) + ? ≈ √(√6571) ≈ √81 = 9. So: 365 = 9 + ?, giving ? = 356. Option C is 356. Let me verify: √99867 = 315.99, ⁴√65547 = 15.97, ∛19712 = 27.02, ⁴√1314 = 6.01. LHS = 315.99 + 15.97 + 27.02 + 6.01 = 365. ⁴√6571 = 8.99. So: 365 = 8.99 + ?, ? = 356.01 ≈ 356. This confirms option C is correct.

Multiple choice
  1. 9

  2. 6

  3. 5

  4. 4

  5. 8

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

Given: (82)^8 ÷ (735)^8 × (731)^6 × 81 = 730^?. This can be rewritten as: (82/735)^8 × (731)^6 × 81 = 730^?. Notice that 82/735 ≈ 1/9 (since 735 ÷ 82 ≈ 9), 731 ≈ 730, and 81 = 3^4. So: (1/9)^8 × 730^6 × 3^4 = 730^?. Simplifying: (1/9)^8 × 3^4 = (1/3^2)^8 × 3^4 = 1/3^16 × 3^4 = 1/3^12. But we need to express this in terms of base 730. Actually, let me think differently. Since 82/735 ≈ 1/9 = 3^(-2), we have: (3^(-2))^8 × 730^6 × 3^4 = 730^? 3^(-16) × 730^6 × 3^4 = 730^? 730^6 × 3^(-12) = 730^?. This doesn't simplify nicely to 730^4. Let me reconsider. Perhaps the question means: 82^8 ÷ 735^8 × 731^6 × 81 = (82/735)^8 × 731^6 × 81. If 82/735 ≈ 1/9, then (1/9)^8 × 730^6 × 81 = 3^(-16) × 730^6 × 3^4 = 730^6 × 3^(-12). For this to be a power of 730, the 3^(-12) must somehow cancel or convert. Actually, if 3^(-12) ≈ 730^(-2) (since 730^2 ≈ 532900, which is not close to 3^12 = 531441, they're very close!), then 730^6 × 730^(-2) = 730^4. Yes! 3^12 = 531441 and 730^2 = 532900, which are very close. So 3^(-12) ≈ 730^(-2). Therefore: 730^6 × 730^(-2) = 730^4. So ? = 4, which is option D.

Multiple choice
  1. $20330$
  2. $12640$
  3. $15000$
  4. $22160$
  5. $19130$
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Approximating: 459% ≈ 4.6, 849.947 ≈ 850, 266% ≈ 2.7, 6284.012 ≈ 6280. 4.6 × 850 = 3910, 2.7 × 6280 = 16956. Sum = 3910 + 16956 - 1486 ≈ 19130. Option E (19130) is closest.

Multiple choice
  1. 23000

  2. 24000

  3. 24500

  4. 25500

  5. 25000

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

Calculate: 7.09% of 8500 ≈ 7% of 8500 = 595. 3.51% of 5500 ≈ 3.5% of 5500 = 192.5. 595 - 192.5 = 402.5. So 1.6% of X = 402.5. Therefore X ≈ 402.5 / 0.016 ≈ 25156, closest to 25000. Option E is correct.

Multiple choice
  1. 2520

  2. 2610

  3. 2750

  4. 2870

  5. 2930

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

Approximate: 118 × 13.5 = 1593 and 170% of 784 = 1.7 × 784 = 1333. Adding: 1593 + 1333 = 2926, which rounds to 2930 (option E). The calculation checks out: 118.07 × 13.49 ≈ 1592 and 169.8% of 784 ≈ 1331, sum ≈ 2923.