It's part of a proportion. The cross products in a proportion are equal. example: 3/4 = 15/20 4x15 = 60 3x20 = 60
3 + 4 + 4 x 15 = 67
60
Actually it is 60 not one. 4x15=60 5x12=60 3x20=60
Level1-4X15 Level2-X4RU
4x15=60 5x12=60
$10-$20
60 6x10=60 5x12=60 4x15=60 2x30=60 3x20=60
4x15=60 and 4x17=64.
1x60 2x30 3x20 4x15 5x12 6x10
i need the front lense for a glenfiel model 200c riflescope
62 explanation is : 4X15+2=62