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Finding the Fourth Proportional to 652.92, 900.78 and 420.12

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Solution

The fourth proportional to 652.92, 900.78 and 420.12 is: 579.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.92 : 900.78 = 420.12 : x
  2. Step 2: Convert to fraction form
    652.92/900.78 = 420.12/x
  3. Step 3: Cross multiply
    652.92x = 900.78 × 420.12
  4. Step 4: Simplify right side
    652.92x = 378,435.69
  5. Step 5: Solve for x
    x = 378,435.69/652.92
  6. Step 6: Final answer
    x = 579.60

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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.