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Finding the Fourth Proportional to 551.40, 759.06 and 420.36

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Solution

The fourth proportional to 551.40, 759.06 and 420.36 is: 578.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    551.40 : 759.06 = 420.36 : x
  2. Step 2: Convert to fraction form
    551.40/759.06 = 420.36/x
  3. Step 3: Cross multiply
    551.40x = 759.06 × 420.36
  4. Step 4: Simplify right side
    551.40x = 319,078.46
  5. Step 5: Solve for x
    x = 319,078.46/551.40
  6. Step 6: Final answer
    x = 578.67

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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.