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Finding the Fourth Proportional to 172.80, 256.80 and 172.80

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Solution

The fourth proportional to 172.80, 256.80 and 172.80 is: 256.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    172.80 : 256.80 = 172.80 : x
  2. Step 2: Convert to fraction form
    172.80/256.80 = 172.80/x
  3. Step 3: Cross multiply
    172.80x = 256.80 × 172.80
  4. Step 4: Simplify right side
    172.80x = 44,375.04
  5. Step 5: Solve for x
    x = 44,375.04/172.80
  6. Step 6: Final answer
    x = 256.80

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.