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Finding the Fourth Proportional to 690.30, 952.56 and 379.80

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Solution

The fourth proportional to 690.30, 952.56 and 379.80 is: 524.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.30 : 952.56 = 379.80 : x
  2. Step 2: Convert to fraction form
    690.30/952.56 = 379.80/x
  3. Step 3: Cross multiply
    690.30x = 952.56 × 379.80
  4. Step 4: Simplify right side
    690.30x = 361,782.29
  5. Step 5: Solve for x
    x = 361,782.29/690.30
  6. Step 6: Final answer
    x = 524.09

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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.