Chapt 3

3.2

1) &average is the location or address on the computer of the

variable average.

3) Address of variables:

#include <stdio.h>

/*Address of variables on the computer*/

main()

{

char *key, *choice;

int *num, *count;

long *ddate;

float *yield;

double *price;

key=&key;

choice=&choice;

num=&num;

count=&count;

ddate=&ddate;

yield=&yield;

price=&price;

printf("The address on the computer of the char variable ""key"" is %c.\n",key);

printf("The address on the computer of the char variable ""choice"" is %c.\n",choice);

printf("The address on the computer of the int variable ""num"" is %d.\n",num);

printf("The address on the computer of the int variable ""count"" is %d.\n",count);

printf("The address on the computer of the long variable ""date"" is %f.\n",ddate);

printf("The address on the computer of the float variable ""yield"" is %f.\n",yield);

printf("The address on the computer of the double variable ""price"" is %f.\n",price);

}

3.3

1)use scanf

a)scanf("%d",&firstnum);

b)scanf("%f",&grade);

c)scanf("%lf",&secnum);

d)scanf("%c",&keyval);

e)scanf("%d %d",&month,&years);

scanf("%f",&average);

f)scanf("%c",&ch);

scanf("%d %d",&num1,&num2);

scanf("%lf",&grade1,&grade2);

g)scanf("%f %f %f",&interest,&principal, &captial);

scanf("%lf %lf",&price,&yield);

h)scanf("%c %c %c",&ch,&letter1,&letter2);

scanf("%d %d %d",&num1,&num2,&num3);

i)scanf("%f %f %f",&temp1,&temp2,&temp3);

scanf("%lf %lf",&volts1,&volts2);

2)declare

a)int day;

b)char fir_char;

c)float grade;

d)long price;

e)int num1,num2;

char ch1;

f)float firstnum, secnum;

int count;

g)char ch1,ch2;

int flag;

long average;

3)fit-it

a)scanf("%d",&num1);

b)scanf("%d %f %lf",&num1,&firstnum, &price);

c)scanf("%d %f %lf",&num1, &secnum, &yield);

d)scanf("%d %d%lf",&num1,&num2, &yield);

e)scanf("%d %d",&num1,&num2);

f)scanf('%d",&num1);

4)

a) #include <stdio.h>

main()

/*Circumference of a circle by Wendi Medley*/

{

float radius;

printf("Please enter the radius of a circle, then hit ""Enter"":");

scanf("%f",&radius);

printf("The circumference is %f",radius*6.2834);

}

4)

b) Test run with 5 as the circumference. 5*6.2834 is 31.417 – It all checks

out.

6)Area of a circle

a)

#include <stdio.h>

main()

/*Area of a room by Wendi Medley*/

{

float length, width;

printf("Please enter length of the room, then hit ""Enter"":");

scanf("%f",&length);

printf("Please enter width of the room, then hit ""Enter"":");

scanf("%f",&width);

printf("The area of the rectangle is %.0f",length*width);

}

b) L=1,w=12 a=12 everything checked out

7)miles per gallon

a) #include <stdio.h>

main()

/*Area of a rectangle by Wendi Medley*/

{

float miles, gas;

printf("Please enter the miles driven, then hit ""Enter"":");

scanf("%f",&miles);

printf("/nPlease enter gallons of gas used,then hit ""Enter"":");

scanf("%f",&gas);

printf("Your car is getting %.2f miles per gallon",miles/gas);

}

b) milage=20 gallons=4, total mpg=5, it’s all good, except for that mph.

9)

a) average of 4 numbers:

#include <stdio.h>

main()

/*Area of a rectangle by Wendi Medley*/

{

float num1,num2,num3,num4, total;

printf("Please enter a number, then hit ""Enter"":\t");

scanf("%f",&num1);

printf("Please enter another number, then hit ""Enter"":\t");

scanf("%f",&num2);

printf("Please enter a third number, then hit ""Enter"":\t");

scanf("%f",&num3);

printf("Please enter the last number, then hit ""Enter"":\t");

scanf("%f",&num4);

printf("The average of all four numbers you entered is:

%.2f.",(num1+num2+num3+num4)/4);

}

b)checked out I entered all my numbers as a 2 and , yep, you guessed it, 2

was my average.

c)using the sum=sum+1 thingy

#include <stdio.h>

main()

/*Area of a rectangle by Wendi Medley*/

{

float number, sum;

printf("Please enter a number, then hit ""Enter"":\t");

scanf("%f",&number);

sum=number;

printf("Please enter another number, then hit ""Enter"":\t");

scanf("%f",&number);

sum=sum+number;

printf("Please enter a third number, then hit ""Enter"":\t");

scanf("%f",&number);

sum=sum+number;

printf("Please enter the last number, then hit ""Enter"":\t");

scanf("%f",&number);

sum=sum+number;

printf("The sum is %f",sum);

}

Need to ask for help an how to work out the average this way