Finding the Fourth Proportional to 77.78, 117.08 and 68.96
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Solution
The fourth proportional to 77.78, 117.08 and 68.96 is: 103.80
Step by Step Solution
- Step 1: Write the proportion equation
77.78 : 117.08 = 68.96 : x - Step 2: Convert to fraction form
77.78/117.08 = 68.96/x - Step 3: Cross multiply
77.78x = 117.08 × 68.96 - Step 4: Simplify right side
77.78x = 8,073.84 - Step 5: Solve for x
x = 8,073.84/77.78 - Step 6: Final answer
x = 103.80
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Why These Related Problems?
These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.