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Finding the Fourth Proportional to 786.51, 1,080.95 and 611.55

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Solution

The fourth proportional to 786.51, 1,080.95 and 611.55 is: 840.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    786.51 : 1,080.95 = 611.55 : x
  2. Step 2: Convert to fraction form
    786.51/1,080.95 = 611.55/x
  3. Step 3: Cross multiply
    786.51x = 1,080.95 × 611.55
  4. Step 4: Simplify right side
    786.51x = 661,051.91
  5. Step 5: Solve for x
    x = 661,051.91/786.51
  6. Step 6: Final answer
    x = 840.49

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.