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Finding the Fourth Proportional to 690, 952.30 and 428.10

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Solution

The fourth proportional to 690, 952.30 and 428.10 is: 590.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    690 : 952.30 = 428.10 : x
  2. Step 2: Convert to fraction form
    690/952.30 = 428.10/x
  3. Step 3: Cross multiply
    690x = 952.30 × 428.10
  4. Step 4: Simplify right side
    690x = 407,679.63
  5. Step 5: Solve for x
    x = 407,679.63/690
  6. Step 6: Final answer
    x = 590.84

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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.