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Finding the Fourth Proportional to 640.25, 883.55 and 419.57

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Solution

The fourth proportional to 640.25, 883.55 and 419.57 is: 579.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.25 : 883.55 = 419.57 : x
  2. Step 2: Convert to fraction form
    640.25/883.55 = 419.57/x
  3. Step 3: Cross multiply
    640.25x = 883.55 × 419.57
  4. Step 4: Simplify right side
    640.25x = 370,711.07
  5. Step 5: Solve for x
    x = 370,711.07/640.25
  6. Step 6: Final answer
    x = 579.01

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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.