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Finding the Fourth Proportional to 906.60, 1,360.12 and 420

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Solution

The fourth proportional to 906.60, 1,360.12 and 420 is: 630.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    906.60 : 1,360.12 = 420 : x
  2. Step 2: Convert to fraction form
    906.60/1,360.12 = 420/x
  3. Step 3: Cross multiply
    906.60x = 1,360.12 × 420
  4. Step 4: Simplify right side
    906.60x = 571,250.40
  5. Step 5: Solve for x
    x = 571,250.40/906.60
  6. Step 6: Final answer
    x = 630.10

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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.