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Finding the Fourth Proportional to 640.12, 955.51 and 549.40

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Solution

The fourth proportional to 640.12, 955.51 and 549.40 is: 820.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.12 : 955.51 = 549.40 : x
  2. Step 2: Convert to fraction form
    640.12/955.51 = 549.40/x
  3. Step 3: Cross multiply
    640.12x = 955.51 × 549.40
  4. Step 4: Simplify right side
    640.12x = 524,957.19
  5. Step 5: Solve for x
    x = 524,957.19/640.12
  6. Step 6: Final answer
    x = 820.09

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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.