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Finding the Fourth Proportional to 565.80, 780.90 and 419.20

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Solution

The fourth proportional to 565.80, 780.90 and 419.20 is: 578.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    565.80 : 780.90 = 419.20 : x
  2. Step 2: Convert to fraction form
    565.80/780.90 = 419.20/x
  3. Step 3: Cross multiply
    565.80x = 780.90 × 419.20
  4. Step 4: Simplify right side
    565.80x = 327,353.28
  5. Step 5: Solve for x
    x = 327,353.28/565.80
  6. Step 6: Final answer
    x = 578.57

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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.