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Finding the Fourth Proportional to 645.42, 890.34 and 468.18

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Solution

The fourth proportional to 645.42, 890.34 and 468.18 is: 645.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.42 : 890.34 = 468.18 : x
  2. Step 2: Convert to fraction form
    645.42/890.34 = 468.18/x
  3. Step 3: Cross multiply
    645.42x = 890.34 × 468.18
  4. Step 4: Simplify right side
    645.42x = 416,839.38
  5. Step 5: Solve for x
    x = 416,839.38/645.42
  6. Step 6: Final answer
    x = 645.84

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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.