A new mixture of self - tanning & moisturizing lotions for everyday use is being developed . This mixture is made by mixing 700 ounces of everyday moisturizing lotion for $0.70 per ounce with self - tanning lotion worth $2 per ounce. If the new self - tanning & moisturizing lotion mixture is to cost $ 1.30 per ounce, how many ounces of the self-tanning lotion should be in the mixture?
The mixture should have ( ) ounces of the self - tanning lotion.