Home / 652.45-978.67-219.91

Finding the Fourth Proportional to 652.45, 978.67 and 219.91

Calculator

Solution

The fourth proportional to 652.45, 978.67 and 219.91 is: 329.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.45 : 978.67 = 219.91 : x
  2. Step 2: Convert to fraction form
    652.45/978.67 = 219.91/x
  3. Step 3: Cross multiply
    652.45x = 978.67 × 219.91
  4. Step 4: Simplify right side
    652.45x = 215,215.31
  5. Step 5: Solve for x
    x = 215,215.31/652.45
  6. Step 6: Final answer
    x = 329.86

Related Problems

Find fourth proportional to 326.22, 489.34 and 109.95
Half scale
Find fourth proportional to 1,304.89, 1,957.34 and 439.81
Double scale
Find fourth proportional to 653.45, 980.17 and 220.91
Similar ratio
Find fourth proportional to 978.67, 1,468.01 and 329.86
1.5x scale

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.