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Finding the Fourth Proportional to 855.40, 1,281.52 and 490.45

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Solution

The fourth proportional to 855.40, 1,281.52 and 490.45 is: 734.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    855.40 : 1,281.52 = 490.45 : x
  2. Step 2: Convert to fraction form
    855.40/1,281.52 = 490.45/x
  3. Step 3: Cross multiply
    855.40x = 1,281.52 × 490.45
  4. Step 4: Simplify right side
    855.40x = 628,521.48
  5. Step 5: Solve for x
    x = 628,521.48/855.40
  6. Step 6: Final answer
    x = 734.77

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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.