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Finding the Fourth Proportional to 665.40, 912.84 and 616.80

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Solution

The fourth proportional to 665.40, 912.84 and 616.80 is: 846.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.40 : 912.84 = 616.80 : x
  2. Step 2: Convert to fraction form
    665.40/912.84 = 616.80/x
  3. Step 3: Cross multiply
    665.40x = 912.84 × 616.80
  4. Step 4: Simplify right side
    665.40x = 563,039.71
  5. Step 5: Solve for x
    x = 563,039.71/665.40
  6. Step 6: Final answer
    x = 846.17

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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.