Finding the Fourth Proportional to 1,380, 1,904.40 and 759
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Solution
The fourth proportional to 1,380, 1,904.40 and 759 is: 1,047.42
Step by Step Solution
- Step 1: Write the proportion equation
1,380 : 1,904.40 = 759 : x - Step 2: Convert to fraction form
1,380/1,904.40 = 759/x - Step 3: Cross multiply
1,380x = 1,904.40 × 759 - Step 4: Simplify right side
1,380x = 1,445,439.60 - Step 5: Solve for x
x = 1,445,439.60/1,380 - Step 6: Final answer
x = 1,047.42
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.