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Finding the Fourth Proportional to 720.10, 991.73 and 669.07

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Solution

The fourth proportional to 720.10, 991.73 and 669.07 is: 921.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.10 : 991.73 = 669.07 : x
  2. Step 2: Convert to fraction form
    720.10/991.73 = 669.07/x
  3. Step 3: Cross multiply
    720.10x = 991.73 × 669.07
  4. Step 4: Simplify right side
    720.10x = 663,535.98
  5. Step 5: Solve for x
    x = 663,535.98/720.10
  6. Step 6: Final answer
    x = 921.45

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1.5x scale

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.