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Finding the Fourth Proportional to 491.40, 738.90 and 412.20

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Solution

The fourth proportional to 491.40, 738.90 and 412.20 is: 619.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.40 : 738.90 = 412.20 : x
  2. Step 2: Convert to fraction form
    491.40/738.90 = 412.20/x
  3. Step 3: Cross multiply
    491.40x = 738.90 × 412.20
  4. Step 4: Simplify right side
    491.40x = 304,574.58
  5. Step 5: Solve for x
    x = 304,574.58/491.40
  6. Step 6: Final answer
    x = 619.81

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.