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Finding the Fourth Proportional to 420.66, 580.69 and 282.74

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Solution

The fourth proportional to 420.66, 580.69 and 282.74 is: 390.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.66 : 580.69 = 282.74 : x
  2. Step 2: Convert to fraction form
    420.66/580.69 = 282.74/x
  3. Step 3: Cross multiply
    420.66x = 580.69 × 282.74
  4. Step 4: Simplify right side
    420.66x = 164,184.29
  5. Step 5: Solve for x
    x = 164,184.29/420.66
  6. Step 6: Final answer
    x = 390.30

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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.