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Finding the Fourth Proportional to 631.80, 870.96 and 521.08

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Solution

The fourth proportional to 631.80, 870.96 and 521.08 is: 718.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.80 : 870.96 = 521.08 : x
  2. Step 2: Convert to fraction form
    631.80/870.96 = 521.08/x
  3. Step 3: Cross multiply
    631.80x = 870.96 × 521.08
  4. Step 4: Simplify right side
    631.80x = 453,839.84
  5. Step 5: Solve for x
    x = 453,839.84/631.80
  6. Step 6: Final answer
    x = 718.33

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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.