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Finding the Fourth Proportional to 491.79, 678.99 and 379.55

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Solution

The fourth proportional to 491.79, 678.99 and 379.55 is: 524.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.79 : 678.99 = 379.55 : x
  2. Step 2: Convert to fraction form
    491.79/678.99 = 379.55/x
  3. Step 3: Cross multiply
    491.79x = 678.99 × 379.55
  4. Step 4: Simplify right side
    491.79x = 257,710.65
  5. Step 5: Solve for x
    x = 257,710.65/491.79
  6. Step 6: Final answer
    x = 524.03

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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.