Home / 643.28-968.42-439.14

Finding the Fourth Proportional to 643.28, 968.42 and 439.14

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Solution

The fourth proportional to 643.28, 968.42 and 439.14 is: 661.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.28 : 968.42 = 439.14 : x
  2. Step 2: Convert to fraction form
    643.28/968.42 = 439.14/x
  3. Step 3: Cross multiply
    643.28x = 968.42 × 439.14
  4. Step 4: Simplify right side
    643.28x = 425,267.12
  5. Step 5: Solve for x
    x = 425,267.12/643.28
  6. Step 6: Final answer
    x = 661.10

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.