Finding the Fourth Proportional to 79.20, 118.98 and 65.70
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Solution
The fourth proportional to 79.20, 118.98 and 65.70 is: 98.70
Step by Step Solution
- Step 1: Write the proportion equation
79.20 : 118.98 = 65.70 : x - Step 2: Convert to fraction form
79.20/118.98 = 65.70/x - Step 3: Cross multiply
79.20x = 118.98 × 65.70 - Step 4: Simplify right side
79.20x = 7,816.99 - Step 5: Solve for x
x = 7,816.99/79.20 - Step 6: Final answer
x = 98.70
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.