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Finding the Fourth Proportional to 521.00, 777.69 and 455.31

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Solution

The fourth proportional to 521.00, 777.69 and 455.31 is: 679.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.00 : 777.69 = 455.31 : x
  2. Step 2: Convert to fraction form
    521.00/777.69 = 455.31/x
  3. Step 3: Cross multiply
    521.00x = 777.69 × 455.31
  4. Step 4: Simplify right side
    521.00x = 354,090.44
  5. Step 5: Solve for x
    x = 354,090.44/521.00
  6. Step 6: Final answer
    x = 679.64

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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.