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Finding the Fourth Proportional to 100.87, 139.23 and 64.01

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Solution

The fourth proportional to 100.87, 139.23 and 64.01 is: 88.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.87 : 139.23 = 64.01 : x
  2. Step 2: Convert to fraction form
    100.87/139.23 = 64.01/x
  3. Step 3: Cross multiply
    100.87x = 139.23 × 64.01
  4. Step 4: Simplify right side
    100.87x = 8,912.11
  5. Step 5: Solve for x
    x = 8,912.11/100.87
  6. Step 6: Final answer
    x = 88.35

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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.