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Finding the Fourth Proportional to 721.80, 995.94 and 500.40

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Solution

The fourth proportional to 721.80, 995.94 and 500.40 is: 690.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.80 : 995.94 = 500.40 : x
  2. Step 2: Convert to fraction form
    721.80/995.94 = 500.40/x
  3. Step 3: Cross multiply
    721.80x = 995.94 × 500.40
  4. Step 4: Simplify right side
    721.80x = 498,368.38
  5. Step 5: Solve for x
    x = 498,368.38/721.80
  6. Step 6: Final answer
    x = 690.45

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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.