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Finding the Fourth Proportional to 661.21, 912.14 and 412.72

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Solution

The fourth proportional to 661.21, 912.14 and 412.72 is: 569.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.21 : 912.14 = 412.72 : x
  2. Step 2: Convert to fraction form
    661.21/912.14 = 412.72/x
  3. Step 3: Cross multiply
    661.21x = 912.14 × 412.72
  4. Step 4: Simplify right side
    661.21x = 376,456.36
  5. Step 5: Solve for x
    x = 376,456.36/661.21
  6. Step 6: Final answer
    x = 569.34

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Double scale
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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.