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Finding the Fourth Proportional to 645.36, 890.64 and 412.08

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Solution

The fourth proportional to 645.36, 890.64 and 412.08 is: 568.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.36 : 890.64 = 412.08 : x
  2. Step 2: Convert to fraction form
    645.36/890.64 = 412.08/x
  3. Step 3: Cross multiply
    645.36x = 890.64 × 412.08
  4. Step 4: Simplify right side
    645.36x = 367,014.93
  5. Step 5: Solve for x
    x = 367,014.93/645.36
  6. Step 6: Final answer
    x = 568.70

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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.