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Finding the Fourth Proportional to 420.80, 578.95 and 368.15

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Solution

The fourth proportional to 420.80, 578.95 and 368.15 is: 506.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.80 : 578.95 = 368.15 : x
  2. Step 2: Convert to fraction form
    420.80/578.95 = 368.15/x
  3. Step 3: Cross multiply
    420.80x = 578.95 × 368.15
  4. Step 4: Simplify right side
    420.80x = 213,136.63
  5. Step 5: Solve for x
    x = 213,136.63/420.80
  6. Step 6: Final answer
    x = 506.51

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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.