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Finding the Fourth Proportional to 661.69, 907.33 and 638.51

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Solution

The fourth proportional to 661.69, 907.33 and 638.51 is: 875.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.69 : 907.33 = 638.51 : x
  2. Step 2: Convert to fraction form
    661.69/907.33 = 638.51/x
  3. Step 3: Cross multiply
    661.69x = 907.33 × 638.51
  4. Step 4: Simplify right side
    661.69x = 579,336.09
  5. Step 5: Solve for x
    x = 579,336.09/661.69
  6. Step 6: Final answer
    x = 875.55

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.