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Finding the Fourth Proportional to 905.19, 1,250.07 and 780.15

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Solution

The fourth proportional to 905.19, 1,250.07 and 780.15 is: 1,077.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    905.19 : 1,250.07 = 780.15 : x
  2. Step 2: Convert to fraction form
    905.19/1,250.07 = 780.15/x
  3. Step 3: Cross multiply
    905.19x = 1,250.07 × 780.15
  4. Step 4: Simplify right side
    905.19x = 975,231.96
  5. Step 5: Solve for x
    x = 975,231.96/905.19
  6. Step 6: Final answer
    x = 1,077.38

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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.