Home / 494.80-681.96-378.64

Finding the Fourth Proportional to 494.80, 681.96 and 378.64

Calculator

Solution

The fourth proportional to 494.80, 681.96 and 378.64 is: 521.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    494.80 : 681.96 = 378.64 : x
  2. Step 2: Convert to fraction form
    494.80/681.96 = 378.64/x
  3. Step 3: Cross multiply
    494.80x = 681.96 × 378.64
  4. Step 4: Simplify right side
    494.80x = 258,217.33
  5. Step 5: Solve for x
    x = 258,217.33/494.80
  6. Step 6: Final answer
    x = 521.86

Related Problems

Find fourth proportional to 247.40, 340.98 and 189.32
Half scale
Find fourth proportional to 989.60, 1,363.92 and 757.28
Double scale
Find fourth proportional to 495.80, 683.34 and 379.64
Similar ratio
Find fourth proportional to 742.20, 1,022.94 and 567.96
1.5x scale

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.