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Finding the Fourth Proportional to 621.50, 857.69 and 345.50

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Solution

The fourth proportional to 621.50, 857.69 and 345.50 is: 476.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.50 : 857.69 = 345.50 : x
  2. Step 2: Convert to fraction form
    621.50/857.69 = 345.50/x
  3. Step 3: Cross multiply
    621.50x = 857.69 × 345.50
  4. Step 4: Simplify right side
    621.50x = 296,331.90
  5. Step 5: Solve for x
    x = 296,331.90/621.50
  6. Step 6: Final answer
    x = 476.80

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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.