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Finding the Fourth Proportional to 661.02, 990.72 and 580.02

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Solution

The fourth proportional to 661.02, 990.72 and 580.02 is: 869.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.02 : 990.72 = 580.02 : x
  2. Step 2: Convert to fraction form
    661.02/990.72 = 580.02/x
  3. Step 3: Cross multiply
    661.02x = 990.72 × 580.02
  4. Step 4: Simplify right side
    661.02x = 574,637.41
  5. Step 5: Solve for x
    x = 574,637.41/661.02
  6. Step 6: Final answer
    x = 869.32

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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.