Gujarat BoardĀ GSEB Textbook Solutions Class 6 Maths Chapter 11 Algebra Ex 11.3 Textbook Questions and Answers.
Gujarat Board Textbook Solutions Class 6 Maths Chapter 11 Algebra Ex 11.3
Question 1.
Makeup as many expressions with numbers {no variables) as you can from three numbers 5, 7, and 8. Every number should be used not more than once. Use only addition, subtraction, and multiplication.
Hint: Three possible expressions are 5 + (8 – 7), 5 – (8 – 7), (5 x 8) + 7; make the other expressions.
Solution:
Here, we have to use the given three numbers altogether. In an expression, every number is not to be used more than once.
Thus, we can have:
(i) 5 + (7 + 8)
(ii) 7 Ć 5 + 8
(iii) (8 – 5) Ć 7
(iv) (7 – 5) Ć 8
(v) (5 Ć 7) – 8
(vi) (8 Ć 7) + 5
(vii) 8 – 5 + 7
(viii) (8 – 7) + 5, etc.
Question 2.
Which out of the following are expressions with numbers only?
(a) y + 3
(b) (7 Ć 20) – 8z
(c) 5(21 -7) + 7 Ć 2
(d) 5
(e) 3x
(f) 5 – 5n
(g) (7 Ć 20) – (5 Ć 10) – 45 + p
Solution:
In expressions (c) and (d) no variable is involved.
āµ (c) and (d) are expressions with numbers only.
Question 3.
Identify the operations (addition, subtraction, division, multiplication) informing the following expressions and tell how the expressions have been formed.
(a) z + 1, z – l, y + 17, y – 17
(b) 17y, \(\frac{y}{17}\), 5z
(c) 2y + 17, 2y – 17
(d) 7m, – 7m + 3, – 7m – 3
Solution:
Question 4.
Give expressions for the following cases.
(a) 7 added to p
(b) 7 subtracted from p
(c) p multiplied by 7
(d) p divided by 7
(e) 7 subtracted from -m
(f) -p multiplied by 5
(g) -p divided by 5
(h) p multiplied by -5
Solution:
(a) P + 7
(b) p – 7
(c) 7p
(d) \(\frac{p}{7}\)
(e) (-m) -7
(f) 5 x (-p) or -5p
(g) \(\frac{-p}{5}\)
(h) -5p
Question 5.
Give expressions in the following cases.
(a) 11 added to 2m
(b) 11 subtracted from 2m
(c) 5 times y to which 3 is added
(d) 5 times y from which 3 is subtracted
(e) y is multiplied by -8
(f) y is multiplied by -8 and then 5 is added to the result
(g) y is multiplied by 5 and the result is subtracted from 16
(h) y is multiplied by -5 and the result is added to 16.
Solution:
(a) 2m + 11
(b) 2m – 11
(c) (5xy) + 3 = 5y + 3
(d) (5 x y) – 3 = 5y – 3
(e) y x (-8) = -8y
(f) [y x (-8)] + 5 = -8y + 5
(g) 16 – (y x 5) = 16 – 5y
(h) 16 + [y x (-5)] = 16 + (-5y)
Question 6.
(a) Form expressions using t and 4. Use not more than one number operation. Every expression must have t in it.
(b) Form expressions using y, 2, and 7. Every expression must have in it. Use only two number operations. These should be different.
Solution:
(a) We can have the following expressions:
t + 4, t – 4, 4t, \(\frac{t}{4}\) , 4 – t…
(b) 2y + 7, 2y – 7, 7y + 2, 7y – 2…