Finding the Fourth Proportional to 83.58, 115.23 and 78.09
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Solution
The fourth proportional to 83.58, 115.23 and 78.09 is: 107.66
Step by Step Solution
- Step 1: Write the proportion equation
83.58 : 115.23 = 78.09 : x - Step 2: Convert to fraction form
83.58/115.23 = 78.09/x - Step 3: Cross multiply
83.58x = 115.23 × 78.09 - Step 4: Simplify right side
83.58x = 8,998.31 - Step 5: Solve for x
x = 8,998.31/83.58 - Step 6: Final answer
x = 107.66
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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.