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Finding the Fourth Proportional to 491.68, 678.33 and 305.11

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Solution

The fourth proportional to 491.68, 678.33 and 305.11 is: 420.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.68 : 678.33 = 305.11 : x
  2. Step 2: Convert to fraction form
    491.68/678.33 = 305.11/x
  3. Step 3: Cross multiply
    491.68x = 678.33 × 305.11
  4. Step 4: Simplify right side
    491.68x = 206,965.27
  5. Step 5: Solve for x
    x = 206,965.27/491.68
  6. Step 6: Final answer
    x = 420.93

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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.