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Finding the Fourth Proportional to 20.77, 31.29 and 20.23

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Solution

The fourth proportional to 20.77, 31.29 and 20.23 is: 30.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.77 : 31.29 = 20.23 : x
  2. Step 2: Convert to fraction form
    20.77/31.29 = 20.23/x
  3. Step 3: Cross multiply
    20.77x = 31.29 × 20.23
  4. Step 4: Simplify right side
    20.77x = 632.90
  5. Step 5: Solve for x
    x = 632.90/20.77
  6. Step 6: Final answer
    x = 30.47

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.