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Finding the Fourth Proportional to 419.50, 578.70 and 272.20

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Solution

The fourth proportional to 419.50, 578.70 and 272.20 is: 375.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.50 : 578.70 = 272.20 : x
  2. Step 2: Convert to fraction form
    419.50/578.70 = 272.20/x
  3. Step 3: Cross multiply
    419.50x = 578.70 × 272.20
  4. Step 4: Simplify right side
    419.50x = 157,522.14
  5. Step 5: Solve for x
    x = 157,522.14/419.50
  6. Step 6: Final answer
    x = 375.50

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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.