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Finding the Fourth Proportional to 521.79, 720.07 and 300.76

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Solution

The fourth proportional to 521.79, 720.07 and 300.76 is: 415.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.79 : 720.07 = 300.76 : x
  2. Step 2: Convert to fraction form
    521.79/720.07 = 300.76/x
  3. Step 3: Cross multiply
    521.79x = 720.07 × 300.76
  4. Step 4: Simplify right side
    521.79x = 216,568.25
  5. Step 5: Solve for x
    x = 216,568.25/521.79
  6. Step 6: Final answer
    x = 415.05

Related Problems

Find fourth proportional to 260.90, 360.04 and 150.38
Half scale
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Double scale
Find fourth proportional to 522.79, 721.45 and 301.76
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.