Class 7 Maths Chapter 4 Simple Equations Exercise 4.4 pdf notes:-
Exercise 4.4 Class 7 maths Chapter 4 Pdf Notes:-
Ncert Solution for Class 7 Maths Chapter 4 Simple Equations Exercise 4.4 Tips:-
APPLICATIONS OF SIMPLE EQUATIONS TO PRACTICAL
We have already seen examples in which we have taken statements in everyday language
and converted them into simple equations. We also have learnt how to solve simple equations.
Thus we are ready to solve puzzles/problems from practical situations. The method is first
to form equations corresponding to such situations and then to solve those equations
to give the solution to the puzzles/problems.
(i) When you multiply a number by 6 and subtract 5 from the product, you get 7. Can you tell what the number is?
(ii) What is that number one third of which added to 5 gives 8?
TRY THESE There are two types of boxes containing mangoes. Each box of the larger type contains
4 more mangoes than the number of mangoes contained in 8 boxes of the smaller type.
Each larger box contains 100 mangoes. Find the number of mangoes contained in the
WHAT HAVE WE DISCUSSED?
1.An equation is a condition on a variable such that two expressions in the variable should have equal value.
2.The value of the variable for which the equation is satisfied is called the solution of the equation.
3.An equation remains the same if the LHS and the RHS are interchanged.
4.In case of the balanced equation, if we
(i) add the same number to both the sides, or (ii) subtract the same number from
both the sides, or (iii) multiply both sides by the same number, or (iv) divide both
sides by the same number, the balance remains undisturbed, i.e., the value of the
LHS remains equal to the value of the RHS
5.The above property gives a systematic method of solving an equation. We carry out
a series of identical mathematical operations on the two sides of the equation in such
a way that on one of the sides we get just the variable. The last step is the solution of
6.Transposing means moving to the other side. Transposition of a number has the same
effect as adding same number to (or subtracting the same number from) both sides of
the equation. When you transpose a number from one side of the equation to the
other side, you change its sign. For example, transposing +3 from the LHS to the
RHS in equation x + 3 = 8 gives x = 8 – 3 (= 5). We can carry out the transposition
of an expression in the same way as the transposition of a number.
7.We have learnt how to construct simple algebraic expressions corresponding to
We also learnt how, using the technique of doing the same mathematical operation
(for example adding the same number) on both sides, we could build an equation
starting from its solution. Further, we also learnt that we could relate a given equation
to some appropriate practical situation and build a practical word problem/puzzle
from the equation.