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Finding the Fourth Proportional to 511.21, 705.40 and 290.12

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Solution

The fourth proportional to 511.21, 705.40 and 290.12 is: 400.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.21 : 705.40 = 290.12 : x
  2. Step 2: Convert to fraction form
    511.21/705.40 = 290.12/x
  3. Step 3: Cross multiply
    511.21x = 705.40 × 290.12
  4. Step 4: Simplify right side
    511.21x = 204,646.40
  5. Step 5: Solve for x
    x = 204,646.40/511.21
  6. Step 6: Final answer
    x = 400.32

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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.