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Finding the Fourth Proportional to 770.80, 1,156.20 and 284.20

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Solution

The fourth proportional to 770.80, 1,156.20 and 284.20 is: 426.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.80 : 1,156.20 = 284.20 : x
  2. Step 2: Convert to fraction form
    770.80/1,156.20 = 284.20/x
  3. Step 3: Cross multiply
    770.80x = 1,156.20 × 284.20
  4. Step 4: Simplify right side
    770.80x = 328,592.04
  5. Step 5: Solve for x
    x = 328,592.04/770.80
  6. Step 6: Final answer
    x = 426.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.