### Algebra-Solutions Ex-11.3

CBSE Class –VI Mathematics
NCERT Solutions
Chaper 11 Algebra (Ex. 11.3)

Question 1. Make up 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)
(a) (8 x 5) – 7
(b) (8 + 5) – 7
(c) (8 x 7) – 5
(d) (8 + 7) – 5
(e) 5 x (7 + 8)
(f) 5 + (7 x 8)
(g) 5 + (8 – 7)
(h) 5 – (7 + 8)
Question 2. Which out of the following are expressions with numbers only:
(a) $y+3$
(b) $\left(7×20\right)-8z$
(c) $5\left(21-7\right)+7×2$
(d) $5$
(e) $3x$
(f) $5-5n$
(g) $\left(7×20\right)-\left(5×10\right)-45+p$
Question 3. Identify the operations (addition, subtraction, division, multiplication) in forming the following expressions and tell how the expressions have been formed:
(a) $z+1,z-1,y+17,y-17$
(b) $17y,\frac{y}{17},5z$
(c) $2y+17,2y-17$
(d) $7m,-7m+3,-7m-3$
(a) $z+1\to$ Addition
$z-1\to$ Subtraction
$y+17\to$ Addition
$y-17\to$ Subtraction
(b) $17y\to$ Multiplication
$\frac{y}{17}\to$ Division
$5z\to$ Multiplication
(c) $2y+17\to$ Multiplication and Addition
$2y-17\to$ Multiplication and Subtraction
(d) $7m\to$ Multiplication
$-7m+3\to$ Multiplication and Addition
$-7m-3\to$ Multiplication and Subtraction
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 $-5.$
(a) $p+7$
(b) $p-7$
(c) $7p$
(d) $\frac{p}{7}$
(e) $-m-7$
(f) $-5p$
(g) $\frac{-p}{5}$
(h) $-5p$
Question 5. Give expression 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 result is subtracted from 16.
(h) $y$ is multiplied by $-5$ and the result is added to 16.
(a) $2m+11$
(b) $2m-11$
(c) $5y+3$
(d) $5y-3$
(e) $-8y$
(f) $-8y+5$
(g) $16-5y$
(h) $-5y+16$
Question 7. (a) From 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 $y$ in it. Use only two number operations. These should be different.
(a) $t+4,t-4,4-t,4t,\frac{t}{4},\frac{4}{t}$
(b) $2y+7,2y-7,7y+2,7y-2$ and so on