9
1 + 2 + 4 + ... + 2n = 2n+1 - 1
Despite conventional wisdom the answer is not 5, it is actually 4.
8
-6
7 + 4 = 11
Nope. Negative 4 plus 6 equals 2. You can see this more easily by rearranging the sum to be 6 - 4 = 2.
You use Plus as a symbol in Maths. Example, 2 Plus 2 equals 4. Or in symbols it would be 2+2=4. __________________________ Plus = + Equals = = (Equals equals =)
the sum of 2 plus 2 is 4/2+2=44
-4 + 7 = 3
24 divided by three equals 8 divided by four equals 6 2 plus 4 equals 6
9 plus 7 equals 144. The series is formed by multiplying the first number with the sum of both numbers. 2(2 + 3 ) = 10 : 7(7 + 2) = 63 : 6(6 + 5) = 66 : 8(8 + 4) = 96 : Then 9(9 + 7) = 144.