Home / 275.19-379.80-209.58

Finding the Fourth Proportional to 275.19, 379.80 and 209.58

Calculator

Solution

The fourth proportional to 275.19, 379.80 and 209.58 is: 289.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    275.19 : 379.80 = 209.58 : x
  2. Step 2: Convert to fraction form
    275.19/379.80 = 209.58/x
  3. Step 3: Cross multiply
    275.19x = 379.80 × 209.58
  4. Step 4: Simplify right side
    275.19x = 79,598.48
  5. Step 5: Solve for x
    x = 79,598.48/275.19
  6. Step 6: Final answer
    x = 289.25

Related Problems

Find fourth proportional to 137.60, 189.90 and 104.79
Half scale
Find fourth proportional to 550.38, 759.60 and 419.16
Double scale
Find fourth proportional to 276.19, 381.18 and 210.58
Similar ratio
Find fourth proportional to 412.79, 569.70 and 314.37
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.