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Finding the Fourth Proportional to 420.86, 578.30 and 377.12

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Solution

The fourth proportional to 420.86, 578.30 and 377.12 is: 518.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.86 : 578.30 = 377.12 : x
  2. Step 2: Convert to fraction form
    420.86/578.30 = 377.12/x
  3. Step 3: Cross multiply
    420.86x = 578.30 × 377.12
  4. Step 4: Simplify right side
    420.86x = 218,088.50
  5. Step 5: Solve for x
    x = 218,088.50/420.86
  6. Step 6: Final answer
    x = 518.20

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.