Home / 1,211.17-1,670.43-812.91

Finding the Fourth Proportional to 1,211.17, 1,670.43 and 812.91

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Solution

The fourth proportional to 1,211.17, 1,670.43 and 812.91 is: 1,121.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.17 : 1,670.43 = 812.91 : x
  2. Step 2: Convert to fraction form
    1,211.17/1,670.43 = 812.91/x
  3. Step 3: Cross multiply
    1,211.17x = 1,670.43 × 812.91
  4. Step 4: Simplify right side
    1,211.17x = 1,357,909.25
  5. Step 5: Solve for x
    x = 1,357,909.25/1,211.17
  6. Step 6: Final answer
    x = 1,121.15

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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.