Home / 1,212.25-1,818.38-390.51

Finding the Fourth Proportional to 1,212.25, 1,818.38 and 390.51

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Solution

The fourth proportional to 1,212.25, 1,818.38 and 390.51 is: 585.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.25 : 1,818.38 = 390.51 : x
  2. Step 2: Convert to fraction form
    1,212.25/1,818.38 = 390.51/x
  3. Step 3: Cross multiply
    1,212.25x = 1,818.38 × 390.51
  4. Step 4: Simplify right side
    1,212.25x = 710,095.57
  5. Step 5: Solve for x
    x = 710,095.57/1,212.25
  6. Step 6: Final answer
    x = 585.77

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Double scale
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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.