Martians have 2 * 3 = <<2*3=6>>6 arms each.
They have 8 / 2 = <<8/2=4>>4 legs each.
Five martians will have 5 * 6 + 5 * 4 = 30 + 20 = <<5*6+5*4=50>>50 limbs.
Five aliens will have 5 * 3 + 5 * 8 = 15 + 40 = <<5*3+5*8=55>>55 limbs.
Five aliens will have 55 - 50 = <<55-50=5>>5 more limbs than five Martians.
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