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Finding the Fourth Proportional to 280.50, 420.12 and 172.06

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Solution

The fourth proportional to 280.50, 420.12 and 172.06 is: 257.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.50 : 420.12 = 172.06 : x
  2. Step 2: Convert to fraction form
    280.50/420.12 = 172.06/x
  3. Step 3: Cross multiply
    280.50x = 420.12 × 172.06
  4. Step 4: Simplify right side
    280.50x = 72,284.80
  5. Step 5: Solve for x
    x = 72,284.80/280.50
  6. Step 6: Final answer
    x = 257.70

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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.