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Finding the Fourth Proportional to 721.90, 995.07 and 689.50

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Solution

The fourth proportional to 721.90, 995.07 and 689.50 is: 950.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.90 : 995.07 = 689.50 : x
  2. Step 2: Convert to fraction form
    721.90/995.07 = 689.50/x
  3. Step 3: Cross multiply
    721.90x = 995.07 × 689.50
  4. Step 4: Simplify right side
    721.90x = 686,100.77
  5. Step 5: Solve for x
    x = 686,100.77/721.90
  6. Step 6: Final answer
    x = 950.41

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1.5x scale

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.