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Finding the Fourth Proportional to 66.32, 90.72 and 65.06

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Solution

The fourth proportional to 66.32, 90.72 and 65.06 is: 89.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.32 : 90.72 = 65.06 : x
  2. Step 2: Convert to fraction form
    66.32/90.72 = 65.06/x
  3. Step 3: Cross multiply
    66.32x = 90.72 × 65.06
  4. Step 4: Simplify right side
    66.32x = 5,902.24
  5. Step 5: Solve for x
    x = 5,902.24/66.32
  6. Step 6: Final answer
    x = 89.00

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.