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Finding the Fourth Proportional to 631.80, 945.30 and 415.80

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Solution

The fourth proportional to 631.80, 945.30 and 415.80 is: 622.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.80 : 945.30 = 415.80 : x
  2. Step 2: Convert to fraction form
    631.80/945.30 = 415.80/x
  3. Step 3: Cross multiply
    631.80x = 945.30 × 415.80
  4. Step 4: Simplify right side
    631.80x = 393,055.74
  5. Step 5: Solve for x
    x = 393,055.74/631.80
  6. Step 6: Final answer
    x = 622.12

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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.