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Finding the Fourth Proportional to 680.98, 939.77 and 419.08

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Solution

The fourth proportional to 680.98, 939.77 and 419.08 is: 578.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.98 : 939.77 = 419.08 : x
  2. Step 2: Convert to fraction form
    680.98/939.77 = 419.08/x
  3. Step 3: Cross multiply
    680.98x = 939.77 × 419.08
  4. Step 4: Simplify right side
    680.98x = 393,838.81
  5. Step 5: Solve for x
    x = 393,838.81/680.98
  6. Step 6: Final answer
    x = 578.34

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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.