Finding the Fourth Proportional to 398.74, 598.01 and 138.70
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Solution
The fourth proportional to 398.74, 598.01 and 138.70 is: 208.02
Step by Step Solution
- Step 1: Write the proportion equation
398.74 : 598.01 = 138.70 : x - Step 2: Convert to fraction form
398.74/598.01 = 138.70/x - Step 3: Cross multiply
398.74x = 598.01 × 138.70 - Step 4: Simplify right side
398.74x = 82,946.99 - Step 5: Solve for x
x = 82,946.99/398.74 - Step 6: Final answer
x = 208.02
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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.