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Finding the Fourth Proportional to 668.24, 920.25 and 666.21

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Solution

The fourth proportional to 668.24, 920.25 and 666.21 is: 917.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.24 : 920.25 = 666.21 : x
  2. Step 2: Convert to fraction form
    668.24/920.25 = 666.21/x
  3. Step 3: Cross multiply
    668.24x = 920.25 × 666.21
  4. Step 4: Simplify right side
    668.24x = 613,079.75
  5. Step 5: Solve for x
    x = 613,079.75/668.24
  6. Step 6: Final answer
    x = 917.45

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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.