If the first three Fibonacci nos. are x1=1, x2=1 and x3=2, what is the value of n for which xn + xn+1 = 89 ?

Three numbers x, y, and z are in the ratio 2: 7: 8. if 12 is subtracted from y, then three numbers form a geometric sequence (in the order x, y–12, z). find x, y, and z. there are 2 sets.

How many kilograms of a 5% salt solution and how many kilograms of a 15% salt solution must be mixed together to make 45kg of an 8% salt solution?

If johnny ate 5 cans of sugar, but in the kitchen they only had 3. what did johnny eat? (he found a secret stash btw.)