Finding the Fourth Proportional to 85.76, 117.99 and 77.99
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Solution
The fourth proportional to 85.76, 117.99 and 77.99 is: 107.30
Step by Step Solution
- Step 1: Write the proportion equation
85.76 : 117.99 = 77.99 : x - Step 2: Convert to fraction form
85.76/117.99 = 77.99/x - Step 3: Cross multiply
85.76x = 117.99 × 77.99 - Step 4: Simplify right side
85.76x = 9,202.04 - Step 5: Solve for x
x = 9,202.04/85.76 - Step 6: Final answer
x = 107.30
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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.