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Finding the Fourth Proportional to 1,370.20, 1,890.48 and 810.40

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Solution

The fourth proportional to 1,370.20, 1,890.48 and 810.40 is: 1,118.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,370.20 : 1,890.48 = 810.40 : x
  2. Step 2: Convert to fraction form
    1,370.20/1,890.48 = 810.40/x
  3. Step 3: Cross multiply
    1,370.20x = 1,890.48 × 810.40
  4. Step 4: Simplify right side
    1,370.20x = 1,532,044.99
  5. Step 5: Solve for x
    x = 1,532,044.99/1,370.20
  6. Step 6: Final answer
    x = 1,118.12

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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.