Home / 1,391.21-1,909.64-1,230.32

Finding the Fourth Proportional to 1,391.21, 1,909.64 and 1,230.32

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Solution

The fourth proportional to 1,391.21, 1,909.64 and 1,230.32 is: 1,688.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,391.21 : 1,909.64 = 1,230.32 : x
  2. Step 2: Convert to fraction form
    1,391.21/1,909.64 = 1,230.32/x
  3. Step 3: Cross multiply
    1,391.21x = 1,909.64 × 1,230.32
  4. Step 4: Simplify right side
    1,391.21x = 2,349,458.74
  5. Step 5: Solve for x
    x = 2,349,458.74/1,391.21
  6. Step 6: Final answer
    x = 1,688.79

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.