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Finding the Fourth Proportional to 1,369.90, 1,890.18 and 810.39

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Solution

The fourth proportional to 1,369.90, 1,890.18 and 810.39 is: 1,118.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,369.90 : 1,890.18 = 810.39 : x
  2. Step 2: Convert to fraction form
    1,369.90/1,890.18 = 810.39/x
  3. Step 3: Cross multiply
    1,369.90x = 1,890.18 × 810.39
  4. Step 4: Simplify right side
    1,369.90x = 1,531,782.97
  5. Step 5: Solve for x
    x = 1,531,782.97/1,369.90
  6. Step 6: Final answer
    x = 1,118.17

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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.