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Finding the Fourth Proportional to 1,387.19, 2,080.49 and 413.07

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Solution

The fourth proportional to 1,387.19, 2,080.49 and 413.07 is: 619.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,387.19 : 2,080.49 = 413.07 : x
  2. Step 2: Convert to fraction form
    1,387.19/2,080.49 = 413.07/x
  3. Step 3: Cross multiply
    1,387.19x = 2,080.49 × 413.07
  4. Step 4: Simplify right side
    1,387.19x = 859,378.14
  5. Step 5: Solve for x
    x = 859,378.14/1,387.19
  6. Step 6: Final answer
    x = 619.51

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.