Home / 1,210.81-1,815.90-388.66

Finding the Fourth Proportional to 1,210.81, 1,815.90 and 388.66

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Solution

The fourth proportional to 1,210.81, 1,815.90 and 388.66 is: 582.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.81 : 1,815.90 = 388.66 : x
  2. Step 2: Convert to fraction form
    1,210.81/1,815.90 = 388.66/x
  3. Step 3: Cross multiply
    1,210.81x = 1,815.90 × 388.66
  4. Step 4: Simplify right side
    1,210.81x = 705,767.69
  5. Step 5: Solve for x
    x = 705,767.69/1,210.81
  6. Step 6: Final answer
    x = 582.89

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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.