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Finding the Fourth Proportional to 70.00, 105.00 and 39.57

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Solution

The fourth proportional to 70.00, 105.00 and 39.57 is: 59.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.00 : 105.00 = 39.57 : x
  2. Step 2: Convert to fraction form
    70.00/105.00 = 39.57/x
  3. Step 3: Cross multiply
    70.00x = 105.00 × 39.57
  4. Step 4: Simplify right side
    70.00x = 4,154.60
  5. Step 5: Solve for x
    x = 4,154.60/70.00
  6. Step 6: Final answer
    x = 59.35

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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.