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Finding the Fourth Proportional to 721.77, 996.03 and 390.19

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Solution

The fourth proportional to 721.77, 996.03 and 390.19 is: 538.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.77 : 996.03 = 390.19 : x
  2. Step 2: Convert to fraction form
    721.77/996.03 = 390.19/x
  3. Step 3: Cross multiply
    721.77x = 996.03 × 390.19
  4. Step 4: Simplify right side
    721.77x = 388,638.47
  5. Step 5: Solve for x
    x = 388,638.47/721.77
  6. Step 6: Final answer
    x = 538.45

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Double scale
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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.