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Finding the Fourth Proportional to 631.28, 870.90 and 369.20

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Solution

The fourth proportional to 631.28, 870.90 and 369.20 is: 509.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.28 : 870.90 = 369.20 : x
  2. Step 2: Convert to fraction form
    631.28/870.90 = 369.20/x
  3. Step 3: Cross multiply
    631.28x = 870.90 × 369.20
  4. Step 4: Simplify right side
    631.28x = 321,536.28
  5. Step 5: Solve for x
    x = 321,536.28/631.28
  6. Step 6: Final answer
    x = 509.34

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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.