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Finding the Fourth Proportional to 1,210.50, 1,815.81 and 388.71

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Solution

The fourth proportional to 1,210.50, 1,815.81 and 388.71 is: 583.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.50 : 1,815.81 = 388.71 : x
  2. Step 2: Convert to fraction form
    1,210.50/1,815.81 = 388.71/x
  3. Step 3: Cross multiply
    1,210.50x = 1,815.81 × 388.71
  4. Step 4: Simplify right side
    1,210.50x = 705,813.79
  5. Step 5: Solve for x
    x = 705,813.79/1,210.50
  6. Step 6: Final answer
    x = 583.08

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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.