32.5k views
0 votes
15X15=?

25X25=?
35X35=?
45X45=?
55x55=?
65X65=?
...
95x95=?
who can tell me how to do these multiplications without a calculator in 30 seconds ?
tell me the details

1 Answer

7 votes
5x5 =25 plus whatever number before the 5 in the equation is added to 25. 15x15= 5x5=25 plus 2 (move to hundredths place) = 225. 25x25 = 5x5=25 plus 4 (move to hundredths place) = 625