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Finding the Fourth Proportional to 609.60, 913.35 and 390.45

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Solution

The fourth proportional to 609.60, 913.35 and 390.45 is: 585.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.60 : 913.35 = 390.45 : x
  2. Step 2: Convert to fraction form
    609.60/913.35 = 390.45/x
  3. Step 3: Cross multiply
    609.60x = 913.35 × 390.45
  4. Step 4: Simplify right side
    609.60x = 356,617.51
  5. Step 5: Solve for x
    x = 356,617.51/609.60
  6. Step 6: Final answer
    x = 585.00

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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.