Home / 1,370.08-2,055.26-639.87

Finding the Fourth Proportional to 1,370.08, 2,055.26 and 639.87

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Solution

The fourth proportional to 1,370.08, 2,055.26 and 639.87 is: 959.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,370.08 : 2,055.26 = 639.87 : x
  2. Step 2: Convert to fraction form
    1,370.08/2,055.26 = 639.87/x
  3. Step 3: Cross multiply
    1,370.08x = 2,055.26 × 639.87
  4. Step 4: Simplify right side
    1,370.08x = 1,315,099.22
  5. Step 5: Solve for x
    x = 1,315,099.22/1,370.08
  6. Step 6: Final answer
    x = 959.87

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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.