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Finding the Fourth Proportional to 906.80, 1,360.16 and 420.24

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Solution

The fourth proportional to 906.80, 1,360.16 and 420.24 is: 630.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    906.80 : 1,360.16 = 420.24 : x
  2. Step 2: Convert to fraction form
    906.80/1,360.16 = 420.24/x
  3. Step 3: Cross multiply
    906.80x = 1,360.16 × 420.24
  4. Step 4: Simplify right side
    906.80x = 571,593.64
  5. Step 5: Solve for x
    x = 571,593.64/906.80
  6. Step 6: Final answer
    x = 630.34

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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.