Finding the Fourth Proportional to 129.70, 178.86 and 107.80
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Solution
The fourth proportional to 129.70, 178.86 and 107.80 is: 148.66
Step by Step Solution
- Step 1: Write the proportion equation
129.70 : 178.86 = 107.80 : x - Step 2: Convert to fraction form
129.70/178.86 = 107.80/x - Step 3: Cross multiply
129.70x = 178.86 × 107.80 - Step 4: Simplify right side
129.70x = 19,281.11 - Step 5: Solve for x
x = 19,281.11/129.70 - Step 6: Final answer
x = 148.66
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.