Home / 680.25-1,018.75-391.08

Finding the Fourth Proportional to 680.25, 1,018.75 and 391.08

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Solution

The fourth proportional to 680.25, 1,018.75 and 391.08 is: 585.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.25 : 1,018.75 = 391.08 : x
  2. Step 2: Convert to fraction form
    680.25/1,018.75 = 391.08/x
  3. Step 3: Cross multiply
    680.25x = 1,018.75 × 391.08
  4. Step 4: Simplify right side
    680.25x = 398,411.70
  5. Step 5: Solve for x
    x = 398,411.70/680.25
  6. Step 6: Final answer
    x = 585.69

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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.