Home / 78,128.36-117,183.24-20,421.80

Finding the Fourth Proportional to 78,128.36, 117,183.24 and 20,421.80

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Solution

The fourth proportional to 78,128.36, 117,183.24 and 20,421.80 is: 30,630.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    78,128.36 : 117,183.24 = 20,421.80 : x
  2. Step 2: Convert to fraction form
    78,128.36/117,183.24 = 20,421.80/x
  3. Step 3: Cross multiply
    78,128.36x = 117,183.24 × 20,421.80
  4. Step 4: Simplify right side
    78,128.36x = 2,393,092,690.63
  5. Step 5: Solve for x
    x = 2,393,092,690.63/78,128.36
  6. Step 6: Final answer
    x = 30,630.27

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1.5x scale

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.