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Finding the Fourth Proportional to 478.90, 660.72 and 304.35

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Solution

The fourth proportional to 478.90, 660.72 and 304.35 is: 419.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.90 : 660.72 = 304.35 : x
  2. Step 2: Convert to fraction form
    478.90/660.72 = 304.35/x
  3. Step 3: Cross multiply
    478.90x = 660.72 × 304.35
  4. Step 4: Simplify right side
    478.90x = 201,090.13
  5. Step 5: Solve for x
    x = 201,090.13/478.90
  6. Step 6: Final answer
    x = 419.90

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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.