Grade 6 : Algebra - Expression - Example problem

1) Which expression represents 5 more than the product of 2 and  y ?

Solution

Product of 2 and y is  2*y or 2y

 5 more than the product of 2y is 2y + 5 or 5 + 2y

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2) Which value of b makes the inequality 3b > 12 true?

a) 2           b)3          c)4          d)5

Solution

Lets assume b=2

Replace b by 2 in 3b > 12

                          3*2 > 12

                           6 > 12 ( which is not true because 6 < 12)

Lets assume b=3

Replace b by 3 in 3b > 12

                          3*3 > 12

                           9 > 12 ( which is not true because 9 < 12)

Lets assume b=4

Replace b by 4 in 3b > 12

                          3*4 > 12

                           12 > 12 ( which is not true because 12 = 12)

Lets assume b=5

Replace b by 5 in 3b > 12

                          3*5 > 12

                           15 > 12 (yes, 15 is greater than 12 which is true)

Answer is d) 5

Grade 7 - Math - Algebra Word problem

The cost of renting a movie is $1.59 for the first two days $0.50 for every day after two days. If Rosy rented a movie and kept it for a week, how much money will she have to pay?

Solution

No.of days Rosy kept the rented movie = 7days (a week)

Cost for the first two days = $1.59
Cost for the remaining 5days = 5*$0.50 

                                           = $2.50

Total amount Rosy has to pay for the rented movie = $1.59 + $2.50 
                                                                          = $4.09

RHCSA Exam Notes : Hard and Soft link in Unix/Linux

 Create Hard links:

Command:

The below command created hardlink called file1.txt for the existing file trial1.txt in /home/student

ln file1.txt /home/student/trial1.txt

Create Soft link:

Command:

The below command created soft link called file1.txt for the existing file trial1.txt in /home/student

ln -s file1.txt /home/student/trial1.txt

Red Hat Certified System Administrator(RHCSA) Exam - Key points(Notes)

 list command in unix : ls

ls

It will show the full list or content of your directory

 

ls -a

In Linux/Unix, hidden files start with . (dot) symbol and they are not visible in the regular directory. The (ls -a) command will enlist the whole list of the current directory including the hidden files.

 

 ls -l

It will show the list in a long list format. 

 

Column 1 : indicates information regarding file permission.
Column 2 : indicates the number of links to the file.
Column 3 & 4 : indicates the owner and group information.
Column 5 : indicates the file size in bytes.
Column 6 : shows the date and time on which the file was recently modified.
Column 7 : shows the file or directory name.

 

ls ~

ls ~ command shows the contents of the home directory

 

 

ls -g

If we don't want to display the owner information in your list, then we can exclude this column with the help of this command. 

 

 

ls -lrt

The ls command is used for listing the contents of a directory. The lrt part is a combination of three different options:

• l: This is for the long listing of the contents. It shows one file in each line with additional info such as permissions, ownership, size, timestamps etc.
• t: This one sorts the long listing output based on time.
• r: This one reverses the order of ls command output.

 

 

 

ls -n

It is used to print group ID and owner ID instead of their names.

 

 

 ls -li

This command prints the index number if file is in the first column.

 

 

 ls -p

It is used to identify the directory easily by marking the directories with a slash (/) line sign.

 

 

ls --version

It checks the version of ls command.