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Finding the Fourth Proportional to 105.09, 145.05 and 70.13

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Solution

The fourth proportional to 105.09, 145.05 and 70.13 is: 96.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    105.09 : 145.05 = 70.13 : x
  2. Step 2: Convert to fraction form
    105.09/145.05 = 70.13/x
  3. Step 3: Cross multiply
    105.09x = 145.05 × 70.13
  4. Step 4: Simplify right side
    105.09x = 10,172.36
  5. Step 5: Solve for x
    x = 10,172.36/105.09
  6. Step 6: Final answer
    x = 96.80

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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.