Finding the Fourth Proportional to 81.14, 121.64 and 56.84
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Solution
The fourth proportional to 81.14, 121.64 and 56.84 is: 85.21
Step by Step Solution
- Step 1: Write the proportion equation
81.14 : 121.64 = 56.84 : x - Step 2: Convert to fraction form
81.14/121.64 = 56.84/x - Step 3: Cross multiply
81.14x = 121.64 × 56.84 - Step 4: Simplify right side
81.14x = 6,913.13 - Step 5: Solve for x
x = 6,913.13/81.14 - Step 6: Final answer
x = 85.21
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.