Home / 1,210.35-1,815.42-388.40

Finding the Fourth Proportional to 1,210.35, 1,815.42 and 388.40

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Solution

The fourth proportional to 1,210.35, 1,815.42 and 388.40 is: 582.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.35 : 1,815.42 = 388.40 : x
  2. Step 2: Convert to fraction form
    1,210.35/1,815.42 = 388.40/x
  3. Step 3: Cross multiply
    1,210.35x = 1,815.42 × 388.40
  4. Step 4: Simplify right side
    1,210.35x = 705,109.13
  5. Step 5: Solve for x
    x = 705,109.13/1,210.35
  6. Step 6: Final answer
    x = 582.57

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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.