115 degrees as 70+40=115 and that is equal to ?
It looks like they're multiplied, then you can simply add the exponents,
b⁸ * b⁴ = b⁸⁺⁴ = b¹²
remember, b⁸=b*b*b*b*b*b*b*b and b⁴=b*b*b*b
so b⁸ * b⁴ = b*b*b*b*b*b*b*b * b*b*b*b = b¹²
Equation::
value + value = value
80x + 60(50-x) = 74*50
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80x + 60*50 - 60x = 74*50
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20x = 14*50
x = 35 lbs (amt. of 80 cent tea to use)
50-x = 15 lbs (amt. of 60 cent tean to use)