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Finding the Fourth Proportional to 660.51, 911.57 and 380.76

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Solution

The fourth proportional to 660.51, 911.57 and 380.76 is: 525.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.51 : 911.57 = 380.76 : x
  2. Step 2: Convert to fraction form
    660.51/911.57 = 380.76/x
  3. Step 3: Cross multiply
    660.51x = 911.57 × 380.76
  4. Step 4: Simplify right side
    660.51x = 347,087.49
  5. Step 5: Solve for x
    x = 347,087.49/660.51
  6. Step 6: Final answer
    x = 525.48

Related Problems

Find fourth proportional to 330.26, 455.78 and 190.38
Half scale
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Double scale
Find fourth proportional to 661.51, 912.95 and 381.76
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.