Let j be the length of Jake's snake and p be length of Penny's snake. We know that j + p = 70, and j = p + 12.
We can substitute the second equation into the first equation to get p + 12 + p = 70
Combining like terms, we get 2p + 12 = 70
Subtracting 12 from both sides, we get 2p = 58
Dividing both sides by 2, we get p = 58 / 2 = <<58/2=29>>29 inches. Penny's snake is 29 inches.
Substituting that length in to the equation j = p + 12, we get j = 29 inches + 12 inches = <<29+12=41>>41 inches
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