Finding the Fourth Proportional to 86.21, 118.71 and 76.49
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Solution
The fourth proportional to 86.21, 118.71 and 76.49 is: 105.33
Step by Step Solution
- Step 1: Write the proportion equation
86.21 : 118.71 = 76.49 : x - Step 2: Convert to fraction form
86.21/118.71 = 76.49/x - Step 3: Cross multiply
86.21x = 118.71 × 76.49 - Step 4: Simplify right side
86.21x = 9,080.13 - Step 5: Solve for x
x = 9,080.13/86.21 - Step 6: Final answer
x = 105.33
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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.