Finding the Fourth Proportional to 77.19, 115.65 and 69.09
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Solution
The fourth proportional to 77.19, 115.65 and 69.09 is: 103.51
Step by Step Solution
- Step 1: Write the proportion equation
77.19 : 115.65 = 69.09 : x - Step 2: Convert to fraction form
77.19/115.65 = 69.09/x - Step 3: Cross multiply
77.19x = 115.65 × 69.09 - Step 4: Simplify right side
77.19x = 7,990.26 - Step 5: Solve for x
x = 7,990.26/77.19 - Step 6: Final answer
x = 103.51
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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.