Finding the Fourth Proportional to 1,260, 1,890 and 394.34
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Solution
The fourth proportional to 1,260, 1,890 and 394.34 is: 591.50
Step by Step Solution
- Step 1: Write the proportion equation
1,260 : 1,890 = 394.34 : x - Step 2: Convert to fraction form
1,260/1,890 = 394.34/x - Step 3: Cross multiply
1,260x = 1,890 × 394.34 - Step 4: Simplify right side
1,260x = 745,293.15 - Step 5: Solve for x
x = 745,293.15/1,260 - Step 6: Final answer
x = 591.50
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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.