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Finding the Fourth Proportional to 690.20, 952.56 and 428.25

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Solution

The fourth proportional to 690.20, 952.56 and 428.25 is: 591.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.20 : 952.56 = 428.25 : x
  2. Step 2: Convert to fraction form
    690.20/952.56 = 428.25/x
  3. Step 3: Cross multiply
    690.20x = 952.56 × 428.25
  4. Step 4: Simplify right side
    690.20x = 407,931.68
  5. Step 5: Solve for x
    x = 407,931.68/690.20
  6. Step 6: Final answer
    x = 591.04

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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.