144
65/65=1+65=66
66 times 6 equals 396.
66 plus 66 equals 132
18 + 10 + 28 + 10 = 66
x = 10
96
26
144
144
1+2+3+... +65 = 65*66/2 = 65*33 = 2145 For the required sum, each term is simply double the corresponding term above, so 2+4+6+... + 130 = 2*2145 = 4290
66
To find the missing number, we first perform the calculation: 83 - 17 equals 66. Then, we need to determine what number plus 56 equals 66. The missing number is 10, because 10 + 56 = 66.