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Finding the Fourth Proportional to 639.89, 883.10 and 360.20

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Solution

The fourth proportional to 639.89, 883.10 and 360.20 is: 497.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.89 : 883.10 = 360.20 : x
  2. Step 2: Convert to fraction form
    639.89/883.10 = 360.20/x
  3. Step 3: Cross multiply
    639.89x = 883.10 × 360.20
  4. Step 4: Simplify right side
    639.89x = 318,089.10
  5. Step 5: Solve for x
    x = 318,089.10/639.89
  6. Step 6: Final answer
    x = 497.10

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1.5x scale

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.