Please help me with 1,2,3,4,5 and show me the steps and the answers do not send me link please

Two blends of tea are mixed to make a blend that will be sold at the fair. black tea sells for $2.20 per pound and orange pekoe tea sells for $3.00 per pound. how much of each should be used to obtain a 4lb blend selling for $2.50 per pound?

Solve this riddle: i am an odd number. i an less than 100. the some of my digit is 12. i am a multiple of 15. what number am i?

The number of calories you burn depends on your weight. a 110-pound person burns 163 calories during 30 minutes of tennis. find the number of calories that a 190-pound person would burn during the same activity, assuming they burn calories at the same rate.