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Finding the Fourth Proportional to 628.84, 870.02 and 551.40

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Solution

The fourth proportional to 628.84, 870.02 and 551.40 is: 762.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.84 : 870.02 = 551.40 : x
  2. Step 2: Convert to fraction form
    628.84/870.02 = 551.40/x
  3. Step 3: Cross multiply
    628.84x = 870.02 × 551.40
  4. Step 4: Simplify right side
    628.84x = 479,729.03
  5. Step 5: Solve for x
    x = 479,729.03/628.84
  6. Step 6: Final answer
    x = 762.88

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.