Answer:
Step-by-step explanation:
Ratio is 7:9
add the ratio it becomes 16
272 members divided by 16
that makes it 17 per one ratio
women ratio is 9
17x9 is 153
i=153 women in the sports club
same thing with ii except it’s divided by 7
91/7 is 13
which means 13 per ratio
there are 9 ratios of women
9x13=117
ii=117 women in a sports club with 91 men with a ratio of 7:9
Answer:
Consider f: N → N defined by f(0)=0 and f(n)=n-1 for all n>0.
Step-by-step explanation:
First we will prove that f is surjective. Let y∈N be any natural number. Define x as the number x=y+1. Then x∈N, and f(x)=x-1=(y+1)-1=y. We conclude that f is surjective.
However, f is not injective. Take x1=0 and x2=1. Then x1≠x2 but f(x1)=0 and f(x2)=x2-1=1-1=0. We have shown that there are two natural numbers x1,x2 such that x1≠x2 but f(x1)=f(x2), that is, f is not injective.
Note:
If 0∉N in your definition of natural numbers, the same reasoning works with the function f: N → N defined by f(1)=1 and f(n)=n-1 for all n>1. The only difference is that you consider x1=1, x2=2 for the injectivity.
Najsjsiskekasizjnsdkdkdkx
