The Bakhshali Manuscript shows that another method for calculating nonperfect squares was being used in India by 400 CE. Use this method to find the approximate value of. The nearest perfect square that is less than 22 is , whose square root is. Add the square root from step 1 to to get 4. 75. Calculate the quantity one-half times the square of divided by the value found in step 2, or 4. 75. Subtract the value found in step 3 from the value found in step 2, or 4. 75. The approximate value of is.