Finding the Fourth Proportional to 1,211.78, 1,817.42 and 345.90
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Solution
The fourth proportional to 1,211.78, 1,817.42 and 345.90 is: 518.78
Step by Step Solution
- Step 1: Write the proportion equation
1,211.78 : 1,817.42 = 345.90 : x - Step 2: Convert to fraction form
1,211.78/1,817.42 = 345.90/x - Step 3: Cross multiply
1,211.78x = 1,817.42 × 345.90 - Step 4: Simplify right side
1,211.78x = 628,645.58 - Step 5: Solve for x
x = 628,645.58/1,211.78 - Step 6: Final answer
x = 518.78
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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.