This is the concept of algebra, suppose that the number of cats is x; number of cats will be x-20 number of rabbits will be 3/2x thus the total number of animals will be: x+(x-20)+3/2x=350 7/2x=350+20 7/2x=370 x=370*2/7 x=105.7=106 therefore we conclude that there we 106 cats in the shelter
