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Finding the Third Proportional to 420.19 and 615.09

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Solution

The third proportional to 420.19 and 615.09 is: 900.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.19 : 615.09 = 615.09 : x
  2. Step 2: Convert to fraction form
    420.19/615.09 = 615.09/x
  3. Step 3: Cross multiply
    420.19x = 615.09 × 615.09
  4. Step 4: Simplify right side
    420.19x = 378,340.32
  5. Step 5: Solve for x
    x = 378,340.32/420.19
  6. Step 6: Final answer
    x = 900.41

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.46) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.