# Time and Work Problems - Shortcut Tricks and Formulas

## Time and Work Problems - Shortcut Tricks and Formulas

Problems Type 1:

A can finish work in X days.

B can finish work in Y days.

Both can finish in Z days = (X*Y) / (X+Y).

Problems Type 2:

Both A and B together can do work in T days.

A can do this work in X days.

then, B can do it in Y days = (X*T) / (X-T)

Problems Type 3:

A can finish work in X days.

B can finish work in Y days.

C can finish work in Z days.

Together they can do work in T days = (X*Y*Z)/ [(X*Y)+(Y*Z)+(X*Z)]

Problems Type 4:

A can finish work in X days.

B can finish work in Y days.

A*X = B*Y

Y = (A*X) / B

Problems Type 5:

A can finish work in X days.

B can finish work in Y days.

A left work after P days then B need to work Q days

Q = [(X - P) / X ] * Y

Problems Type 6:

M1 person can do W1 work in D1 days and H1 hours

M2 person can do W2 work in D2 days and H2 hours

M1D1H1 = M2D2H2  Time and Work Problems - Shortcut Tricks and Formulas

Problems Type 1: .

A can finish work in X days. .

B can finish work in Y days.

Both can finish in Z days = (X*Y) / (X+Y). .

Problems Type 2: .

Both A and B together can do work in T days.

A can do this work in X days.

then, B can do it in Y days = (X*T) / (X-T) .

Problems Type 3: .

A can finish work in X days.

B can finish work in Y days.

C can finish work in Z days.

Together they can do work in T days = (X*Y*Z)/ [(X*Y)+(Y*Z)+(X*Z)] .

Problems Type 4: .

A can finish work in X days.

B can finish work in Y days.

A*X = B*Y.

...

Average calculation

N = the number of terms  .

S = the sum of the numbers in the set.

Average = S/N .

For example.

The marks of a student in five subjects are 96, 94, 92, 87, and 81, then what is the average score of the student?.

N = 5.

S = 96 + 94 + 92 + 87 + 81 = 450.

A = 450/5 = 90.

Another type questions .

1). There are 36 boys and 44 girls in a class. The average score of boys is 40 and girls are 35. Then what will be the average mark? .

Total mark of 36 boys = 36 x 40 = 1440.

Total mark of 44 girls = 35 x 44 = 1540.

Total mark of 80 Students = 1440 + 1540 = 2980 .

Average mark of the class = (2980 / 80).

...

Divisibility Rule

What is the divisibility by 2 Rule?.
Even numbers are multiples of 2. A number is even if ends in 0,2,4,6, or 8.
What is the divisibility by 3 rule?.
A number is divisible by 3 if the sum of its digits is divisible by 3.
372, for instance, is divisible by 3 since sum of its digits (3+7+2) is 12. And 12 is divisible by 3.
What is the divisibility by 4 rule?.
A number is divisible by 4 if the number\'s  last two digits are divisible by 4.
9,312, for instance, is divisible by 4 since its last 2 digits are 12. And 12 is divisible by 4.
What is the divisibility by 5 rule?.
A number is divisible by 5 if its last digit is a 0 or 5.
What is the divisibility by 6 rule?.
Since 6 is a multiple of 2 and 3, the rules for divisibility by 6 are a combination of the rule for 2 and the rule for   3.
Divisibility by 8 Rule.
A number passes the test for 8 if the las...  #### Secretariat Assistant Syllabus 2021 #### LDC Syllabus 2022 #### Tenth Level Mains Syllabus #### Secretariat Assistant Previous Question paper #### Secretariat Assistant Syllabus 2021 #### 10th level Preliminary Exam Previous Year Question Paper #### LDC Previous Question papers #### LGS Previous Question papers #### Village Field Assistant Previous Question papers #### Preliminary Exam Answer key 2021 #### Fireman Previous year Question Papers #### UPSA Previous Question papers #### LPSA Previous Question papers   