Home / 1,421.80-2,133.30-691.38

Finding the Fourth Proportional to 1,421.80, 2,133.30 and 691.38

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Solution

The fourth proportional to 1,421.80, 2,133.30 and 691.38 is: 1,037.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,421.80 : 2,133.30 = 691.38 : x
  2. Step 2: Convert to fraction form
    1,421.80/2,133.30 = 691.38/x
  3. Step 3: Cross multiply
    1,421.80x = 2,133.30 × 691.38
  4. Step 4: Simplify right side
    1,421.80x = 1,474,920.95
  5. Step 5: Solve for x
    x = 1,474,920.95/1,421.80
  6. Step 6: Final answer
    x = 1,037.36

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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.