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Finding the Fourth Proportional to 479.40, 661.49 and 282.90

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Solution

The fourth proportional to 479.40, 661.49 and 282.90 is: 390.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.40 : 661.49 = 282.90 : x
  2. Step 2: Convert to fraction form
    479.40/661.49 = 282.90/x
  3. Step 3: Cross multiply
    479.40x = 661.49 × 282.90
  4. Step 4: Simplify right side
    479.40x = 187,134.11
  5. Step 5: Solve for x
    x = 187,134.11/479.40
  6. Step 6: Final answer
    x = 390.35

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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.