Home / 1,438.32-2,154.38-821.70

Finding the Fourth Proportional to 1,438.32, 2,154.38 and 821.70

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Solution

The fourth proportional to 1,438.32, 2,154.38 and 821.70 is: 1,230.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,438.32 : 2,154.38 = 821.70 : x
  2. Step 2: Convert to fraction form
    1,438.32/2,154.38 = 821.70/x
  3. Step 3: Cross multiply
    1,438.32x = 2,154.38 × 821.70
  4. Step 4: Simplify right side
    1,438.32x = 1,770,254.05
  5. Step 5: Solve for x
    x = 1,770,254.05/1,438.32
  6. Step 6: Final answer
    x = 1,230.78

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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.