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Finding the Fourth Proportional to 636.80, 955.20 and 631.40

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Solution

The fourth proportional to 636.80, 955.20 and 631.40 is: 947.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.80 : 955.20 = 631.40 : x
  2. Step 2: Convert to fraction form
    636.80/955.20 = 631.40/x
  3. Step 3: Cross multiply
    636.80x = 955.20 × 631.40
  4. Step 4: Simplify right side
    636.80x = 603,113.28
  5. Step 5: Solve for x
    x = 603,113.28/636.80
  6. Step 6: Final answer
    x = 947.10

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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.