Answer:
3400
Step-by-step explanation:
60 * 70 = 4200
70 - 10 - 20 = 40
20 * 40 = 800
4200 - 800 = 3400
3,400
I did 70 times 60 which gave me 4,200 then with the 10 and 20 I subtracted it to 70 and did 20 times 40 that gave me 800 then subtracted that by 4200 then it gave me 3,400.
