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Finding the Fourth Proportional to 1,378.03, 1,901.21 and 788.15

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Solution

The fourth proportional to 1,378.03, 1,901.21 and 788.15 is: 1,087.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,378.03 : 1,901.21 = 788.15 : x
  2. Step 2: Convert to fraction form
    1,378.03/1,901.21 = 788.15/x
  3. Step 3: Cross multiply
    1,378.03x = 1,901.21 × 788.15
  4. Step 4: Simplify right side
    1,378.03x = 1,498,438.66
  5. Step 5: Solve for x
    x = 1,498,438.66/1,378.03
  6. Step 6: Final answer
    x = 1,087.38

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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.