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Finding the Fourth Proportional to 720.64, 992.88 and 637.60

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Solution

The fourth proportional to 720.64, 992.88 and 637.60 is: 878.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.64 : 992.88 = 637.60 : x
  2. Step 2: Convert to fraction form
    720.64/992.88 = 637.60/x
  3. Step 3: Cross multiply
    720.64x = 992.88 × 637.60
  4. Step 4: Simplify right side
    720.64x = 633,060.29
  5. Step 5: Solve for x
    x = 633,060.29/720.64
  6. Step 6: Final answer
    x = 878.47

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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.