Home / 1,421.38-2,130.26-640.54

Finding the Fourth Proportional to 1,421.38, 2,130.26 and 640.54

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Solution

The fourth proportional to 1,421.38, 2,130.26 and 640.54 is: 959.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,421.38 : 2,130.26 = 640.54 : x
  2. Step 2: Convert to fraction form
    1,421.38/2,130.26 = 640.54/x
  3. Step 3: Cross multiply
    1,421.38x = 2,130.26 × 640.54
  4. Step 4: Simplify right side
    1,421.38x = 1,364,516.74
  5. Step 5: Solve for x
    x = 1,364,516.74/1,421.38
  6. Step 6: Final answer
    x = 959.99

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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.