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Finding the Fourth Proportional to 419.40, 577.08 and 378

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Solution

The fourth proportional to 419.40, 577.08 and 378 is: 520.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.40 : 577.08 = 378 : x
  2. Step 2: Convert to fraction form
    419.40/577.08 = 378/x
  3. Step 3: Cross multiply
    419.40x = 577.08 × 378
  4. Step 4: Simplify right side
    419.40x = 218,136.24
  5. Step 5: Solve for x
    x = 218,136.24/419.40
  6. Step 6: Final answer
    x = 520.12

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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.