sin 16 $\pi$ /2
2+4-23%2+12
8.40 is what percent of 8?
1/0.025
x+7:2(x+14) in the duplicate ratio of 5:8, find x
x-12=5x-2
4.6t+8.1u=104
3.8t-2.7u=-8
x(x+1)+72/x(x+1)=18
How many of the triple permutations of the set A={a,b,c,d,e} contain at least one vowel?