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Finding the Fourth Proportional to 491.39, 678.23 and 304.76

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Solution

The fourth proportional to 491.39, 678.23 and 304.76 is: 420.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.39 : 678.23 = 304.76 : x
  2. Step 2: Convert to fraction form
    491.39/678.23 = 304.76/x
  3. Step 3: Cross multiply
    491.39x = 678.23 × 304.76
  4. Step 4: Simplify right side
    491.39x = 206,692.46
  5. Step 5: Solve for x
    x = 206,692.46/491.39
  6. Step 6: Final answer
    x = 420.63

Related Problems

Find fourth proportional to 245.69, 339.11 and 152.38
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Double scale
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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.