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Finding the Fourth Proportional to 807.07, 1,210.61 and 287.05

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Solution

The fourth proportional to 807.07, 1,210.61 and 287.05 is: 430.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.07 : 1,210.61 = 287.05 : x
  2. Step 2: Convert to fraction form
    807.07/1,210.61 = 287.05/x
  3. Step 3: Cross multiply
    807.07x = 1,210.61 × 287.05
  4. Step 4: Simplify right side
    807.07x = 347,501.14
  5. Step 5: Solve for x
    x = 347,501.14/807.07
  6. Step 6: Final answer
    x = 430.57

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.