Home / 1,328.56-1,991.82-869.20

Finding the Fourth Proportional to 1,328.56, 1,991.82 and 869.20

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Solution

The fourth proportional to 1,328.56, 1,991.82 and 869.20 is: 1,303.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,328.56 : 1,991.82 = 869.20 : x
  2. Step 2: Convert to fraction form
    1,328.56/1,991.82 = 869.20/x
  3. Step 3: Cross multiply
    1,328.56x = 1,991.82 × 869.20
  4. Step 4: Simplify right side
    1,328.56x = 1,731,289.94
  5. Step 5: Solve for x
    x = 1,731,289.94/1,328.56
  6. Step 6: Final answer
    x = 1,303.13

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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.