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Finding the Fourth Proportional to 890.76, 1,229.10 and 517.80

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Solution

The fourth proportional to 890.76, 1,229.10 and 517.80 is: 714.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.76 : 1,229.10 = 517.80 : x
  2. Step 2: Convert to fraction form
    890.76/1,229.10 = 517.80/x
  3. Step 3: Cross multiply
    890.76x = 1,229.10 × 517.80
  4. Step 4: Simplify right side
    890.76x = 636,427.98
  5. Step 5: Solve for x
    x = 636,427.98/890.76
  6. Step 6: Final answer
    x = 714.48

Related Problems

Find fourth proportional to 445.38, 614.55 and 258.90
Half scale
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Double scale
Find fourth proportional to 891.76, 1,230.48 and 518.80
Similar ratio
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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.