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Finding the Fourth Proportional to 491.58, 678.51 and 305.04

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Solution

The fourth proportional to 491.58, 678.51 and 305.04 is: 421.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.58 : 678.51 = 305.04 : x
  2. Step 2: Convert to fraction form
    491.58/678.51 = 305.04/x
  3. Step 3: Cross multiply
    491.58x = 678.51 × 305.04
  4. Step 4: Simplify right side
    491.58x = 206,972.69
  5. Step 5: Solve for x
    x = 206,972.69/491.58
  6. Step 6: Final answer
    x = 421.04

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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.