Mine

irb(main):081:0* (0..99).to_a.every(2) { |x,y|
irb(main):082:1* puts [x, y].inspect
irb(main):083:1> }
[0, 1]
[2, 3]
[4, 5]
[6, 7]
[8, 9]
[10, 11]
[12, 13]
[14, 15]
[16, 17]
[18, 19]
[20, 21]
[22, 23]
[24, 25]
[26, 27]
[28, 29]
[30, 31]
[32, 33]
[34, 35]
[36, 37]
[38, 39]
[40, 41]
[42, 43]
[44, 45]
[46, 47]
[48, 49]
[50, 51]
[52, 53]
[54, 55]
[56, 57]
[58, 59]
[60, 61]
[62, 63]
[64, 65]
[66, 67]
[68, 69]
[70, 71]
[72, 73]
[74, 75]
[76, 77]
[78, 79]
[80, 81]
[82, 83]
[84, 85]
[86, 87]
[88, 89]
[90, 91]
[92, 93]
[94, 95]
[96, 97]
[98, 99]
=> 50


irb(main):087:0> (0..99).to_a.every(3) { |x,y,z|
irb(main):088:1* puts [x, y,z].inspect
irb(main):089:1> }
[0, 1, 2]
[3, 4, 5]
[6, 7, 8]
[9, 10, 11]
[12, 13, 14]
[15, 16, 17]
[18, 19, 20]
[21, 22, 23]
[24, 25, 26]
[27, 28, 29]
[30, 31, 32]
[33, 34, 35]
[36, 37, 38]
[39, 40, 41]
[42, 43, 44]
[45, 46, 47]
[48, 49, 50]
[51, 52, 53]
[54, 55, 56]
[57, 58, 59]
[60, 61, 62]
[63, 64, 65]
[66, 67, 68]
[69, 70, 71]
[72, 73, 74]
[75, 76, 77]
[78, 79, 80]
[81, 82, 83]
[84, 85, 86]
[87, 88, 89]
[90, 91, 92]
[93, 94, 95]
[96, 97, 98]
=> 33
irb(main):090:0>