Finding the Fourth Proportional to 45.47, 68.18 and 21.09
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Solution
The fourth proportional to 45.47, 68.18 and 21.09 is: 31.62
Step by Step Solution
- Step 1: Write the proportion equation
45.47 : 68.18 = 21.09 : x - Step 2: Convert to fraction form
45.47/68.18 = 21.09/x - Step 3: Cross multiply
45.47x = 68.18 × 21.09 - Step 4: Simplify right side
45.47x = 1,437.81 - Step 5: Solve for x
x = 1,437.81/45.47 - Step 6: Final answer
x = 31.62
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.