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Finding the Fourth Proportional to 661.68, 991.54 and 368.78

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Solution

The fourth proportional to 661.68, 991.54 and 368.78 is: 552.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.68 : 991.54 = 368.78 : x
  2. Step 2: Convert to fraction form
    661.68/991.54 = 368.78/x
  3. Step 3: Cross multiply
    661.68x = 991.54 × 368.78
  4. Step 4: Simplify right side
    661.68x = 365,655.16
  5. Step 5: Solve for x
    x = 365,655.16/661.68
  6. Step 6: Final answer
    x = 552.62

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.