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Finding the Fourth Proportional to 631.21, 870.41 and 498.21

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Solution

The fourth proportional to 631.21, 870.41 and 498.21 is: 687.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.21 : 870.41 = 498.21 : x
  2. Step 2: Convert to fraction form
    631.21/870.41 = 498.21/x
  3. Step 3: Cross multiply
    631.21x = 870.41 × 498.21
  4. Step 4: Simplify right side
    631.21x = 433,647.98
  5. Step 5: Solve for x
    x = 433,647.98/631.21
  6. Step 6: Final answer
    x = 687.01

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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.