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Finding the Fourth Proportional to 21.28, 29.38 and 19

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Solution

The fourth proportional to 21.28, 29.38 and 19 is: 26.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.28 : 29.38 = 19 : x
  2. Step 2: Convert to fraction form
    21.28/29.38 = 19/x
  3. Step 3: Cross multiply
    21.28x = 29.38 × 19
  4. Step 4: Simplify right side
    21.28x = 558.22
  5. Step 5: Solve for x
    x = 558.22/21.28
  6. Step 6: Final answer
    x = 26.23

Related Problems

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.