Home / 819-1,228.50-211

Finding the Fourth Proportional to 819, 1,228.50 and 211

Calculator

Solution

The fourth proportional to 819, 1,228.50 and 211 is: 316.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    819 : 1,228.50 = 211 : x
  2. Step 2: Convert to fraction form
    819/1,228.50 = 211/x
  3. Step 3: Cross multiply
    819x = 1,228.50 × 211
  4. Step 4: Simplify right side
    819x = 259,213.50
  5. Step 5: Solve for x
    x = 259,213.50/819
  6. Step 6: Final answer
    x = 316.50

Related Problems

Find fourth proportional to 409.50, 614.25 and 105.50
Half scale
Find fourth proportional to 1,638, 2,457 and 422
Double scale
Find fourth proportional to 820, 1,230 and 212
Similar ratio
Find fourth proportional to 1,228.50, 1,842.75 and 316.50
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.