Estimate 43/81 by using compatible numbers
Suppose you are asked to evaluate a quotient like 923/462. You have several options. You could choose 900 and 500 as compatible numbers for the two given numbers and then your estimated quotient would be 900/500 = 1.8. Or You could choose 920 and 460 as the compatible numbers for them and then your estimated quotient would be 920/460 = 2.0. So the question is essentially, what compatible numbers did you pick and using them, what was the quotient. There is no correct answer to picking compatible numbers. Any estimation is a trade-off between simplicity and accuracy. Incidentally, a more accurate answer is 1.9978 (approx), but even that is not perfect!
i think it is 28x26
300 + 60
280 + 500 = 780