Home / 1,247.40-1,871.10-919.35

Finding the Fourth Proportional to 1,247.40, 1,871.10 and 919.35

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Solution

The fourth proportional to 1,247.40, 1,871.10 and 919.35 is: 1,379.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,247.40 : 1,871.10 = 919.35 : x
  2. Step 2: Convert to fraction form
    1,247.40/1,871.10 = 919.35/x
  3. Step 3: Cross multiply
    1,247.40x = 1,871.10 × 919.35
  4. Step 4: Simplify right side
    1,247.40x = 1,720,195.79
  5. Step 5: Solve for x
    x = 1,720,195.79/1,247.40
  6. Step 6: Final answer
    x = 1,379.03

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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.