Home / 1,311.18-1,810.19-869.69

Finding the Fourth Proportional to 1,311.18, 1,810.19 and 869.69

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Solution

The fourth proportional to 1,311.18, 1,810.19 and 869.69 is: 1,200.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,311.18 : 1,810.19 = 869.69 : x
  2. Step 2: Convert to fraction form
    1,311.18/1,810.19 = 869.69/x
  3. Step 3: Cross multiply
    1,311.18x = 1,810.19 × 869.69
  4. Step 4: Simplify right side
    1,311.18x = 1,574,290.74
  5. Step 5: Solve for x
    x = 1,574,290.74/1,311.18
  6. Step 6: Final answer
    x = 1,200.67

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.