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Finding the Fourth Proportional to 629.66, 870 and 499.80

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Solution

The fourth proportional to 629.66, 870 and 499.80 is: 690.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.66 : 870 = 499.80 : x
  2. Step 2: Convert to fraction form
    629.66/870 = 499.80/x
  3. Step 3: Cross multiply
    629.66x = 870 × 499.80
  4. Step 4: Simplify right side
    629.66x = 434,826
  5. Step 5: Solve for x
    x = 434,826/629.66
  6. Step 6: Final answer
    x = 690.57

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.