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Finding the Fourth Proportional to 911.80, 1,368.30 and 521.80

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Solution

The fourth proportional to 911.80, 1,368.30 and 521.80 is: 783.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    911.80 : 1,368.30 = 521.80 : x
  2. Step 2: Convert to fraction form
    911.80/1,368.30 = 521.80/x
  3. Step 3: Cross multiply
    911.80x = 1,368.30 × 521.80
  4. Step 4: Simplify right side
    911.80x = 713,978.94
  5. Step 5: Solve for x
    x = 713,978.94/911.80
  6. Step 6: Final answer
    x = 783.04

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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.