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Finding the Fourth Proportional to 385.06, 531.72 and 280.74

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Solution

The fourth proportional to 385.06, 531.72 and 280.74 is: 387.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.06 : 531.72 = 280.74 : x
  2. Step 2: Convert to fraction form
    385.06/531.72 = 280.74/x
  3. Step 3: Cross multiply
    385.06x = 531.72 × 280.74
  4. Step 4: Simplify right side
    385.06x = 149,275.07
  5. Step 5: Solve for x
    x = 149,275.07/385.06
  6. Step 6: Final answer
    x = 387.67

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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.