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Finding the Fourth Proportional to 840.08, 1,159.28 and 490.64

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Solution

The fourth proportional to 840.08, 1,159.28 and 490.64 is: 677.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.08 : 1,159.28 = 490.64 : x
  2. Step 2: Convert to fraction form
    840.08/1,159.28 = 490.64/x
  3. Step 3: Cross multiply
    840.08x = 1,159.28 × 490.64
  4. Step 4: Simplify right side
    840.08x = 568,789.14
  5. Step 5: Solve for x
    x = 568,789.14/840.08
  6. Step 6: Final answer
    x = 677.07

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1.5x scale

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.