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Finding the Fourth Proportional to 1,813.86, 2,720.25 and 643.65

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Solution

The fourth proportional to 1,813.86, 2,720.25 and 643.65 is: 965.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,813.86 : 2,720.25 = 643.65 : x
  2. Step 2: Convert to fraction form
    1,813.86/2,720.25 = 643.65/x
  3. Step 3: Cross multiply
    1,813.86x = 2,720.25 × 643.65
  4. Step 4: Simplify right side
    1,813.86x = 1,750,878.71
  5. Step 5: Solve for x
    x = 1,750,878.71/1,813.86
  6. Step 6: Final answer
    x = 965.28

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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.