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Finding the Fourth Proportional to 806.55, 1,210.02 and 258.78

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Solution

The fourth proportional to 806.55, 1,210.02 and 258.78 is: 388.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.55 : 1,210.02 = 258.78 : x
  2. Step 2: Convert to fraction form
    806.55/1,210.02 = 258.78/x
  3. Step 3: Cross multiply
    806.55x = 1,210.02 × 258.78
  4. Step 4: Simplify right side
    806.55x = 313,128.98
  5. Step 5: Solve for x
    x = 313,128.98/806.55
  6. Step 6: Final answer
    x = 388.23

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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.