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Finding the Fourth Proportional to 770.64, 1,063.24 and 490.80

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Solution

The fourth proportional to 770.64, 1,063.24 and 490.80 is: 677.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.64 : 1,063.24 = 490.80 : x
  2. Step 2: Convert to fraction form
    770.64/1,063.24 = 490.80/x
  3. Step 3: Cross multiply
    770.64x = 1,063.24 × 490.80
  4. Step 4: Simplify right side
    770.64x = 521,838.19
  5. Step 5: Solve for x
    x = 521,838.19/770.64
  6. Step 6: Final answer
    x = 677.15

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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.