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Finding the Fourth Proportional to 720.52, 995.40 and 642.12

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Solution

The fourth proportional to 720.52, 995.40 and 642.12 is: 887.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.52 : 995.40 = 642.12 : x
  2. Step 2: Convert to fraction form
    720.52/995.40 = 642.12/x
  3. Step 3: Cross multiply
    720.52x = 995.40 × 642.12
  4. Step 4: Simplify right side
    720.52x = 639,166.25
  5. Step 5: Solve for x
    x = 639,166.25/720.52
  6. Step 6: Final answer
    x = 887.09

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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.