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Finding the Fourth Proportional to 720.19, 993.89 and 409.69

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Solution

The fourth proportional to 720.19, 993.89 and 409.69 is: 565.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.19 : 993.89 = 409.69 : x
  2. Step 2: Convert to fraction form
    720.19/993.89 = 409.69/x
  3. Step 3: Cross multiply
    720.19x = 993.89 × 409.69
  4. Step 4: Simplify right side
    720.19x = 407,186.79
  5. Step 5: Solve for x
    x = 407,186.79/720.19
  6. Step 6: Final answer
    x = 565.39

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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.