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Finding the Fourth Proportional to 419.40, 578.58 and 386.12

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Solution

The fourth proportional to 419.40, 578.58 and 386.12 is: 532.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.40 : 578.58 = 386.12 : x
  2. Step 2: Convert to fraction form
    419.40/578.58 = 386.12/x
  3. Step 3: Cross multiply
    419.40x = 578.58 × 386.12
  4. Step 4: Simplify right side
    419.40x = 223,401.31
  5. Step 5: Solve for x
    x = 223,401.31/419.40
  6. Step 6: Final answer
    x = 532.67

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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.