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Finding the Fourth Proportional to 670.30, 999.80 and 649.80

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Solution

The fourth proportional to 670.30, 999.80 and 649.80 is: 969.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    670.30 : 999.80 = 649.80 : x
  2. Step 2: Convert to fraction form
    670.30/999.80 = 649.80/x
  3. Step 3: Cross multiply
    670.30x = 999.80 × 649.80
  4. Step 4: Simplify right side
    670.30x = 649,666.87
  5. Step 5: Solve for x
    x = 649,666.87/670.30
  6. Step 6: Final answer
    x = 969.22

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.