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Finding the Fourth Proportional to 657.60, 989.52 and 618.72

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Solution

The fourth proportional to 657.60, 989.52 and 618.72 is: 931.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.60 : 989.52 = 618.72 : x
  2. Step 2: Convert to fraction form
    657.60/989.52 = 618.72/x
  3. Step 3: Cross multiply
    657.60x = 989.52 × 618.72
  4. Step 4: Simplify right side
    657.60x = 612,235.81
  5. Step 5: Solve for x
    x = 612,235.81/657.60
  6. Step 6: Final answer
    x = 931.02

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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.