Page 98 - Maths Class 06

EXAMPLE 4. Simplify: (-18 ) (+ -60 ) (- -40 ) (+ -70 ) (- +10 )
SOLUTION : We rewrite the expression as:
-18 60 + 40 70 10 = -( 18 60 70 10 ) + 40
-
-
-
-
-
-
= -( 158 ) + 40
= -118
EXAMPLE 5. Subtract:
(a) the sum of -17 and +50 from -21
(b) the sum of -11 and -31 from the difference (20 - 40 )
SOLUTION : (a) The sum of -17 and +50 is +33.

-
\ (-21 ) (- +33 ) = -21 33 = -54
(b) The sum of -11 and -31 is -42
\ (20 - 40 ) ( 42- - ) = 20 - 40 + 42
= 62 40
-
= 22
EXAMPLE 6. If the sum of two integers is -72 and one of the integer is -37, what is the other integer?
SOLUTION : The other integer = sum of two integers – given integer

= -( 72 ) - -( 37 )
= -72 37 = -35
+
EXAMPLE 7. A point X on the top of the mountain is 5600 m above the sea level and a point Y is 3600 m
below the sea level. Find the vertical distance between the points X and Y.

SOLUTION : The vertical distance between points X and Y =(5600 + 3600 m = 9200 m
)

Exercise 6.3

1. Subtract:
(a) 0 from -52 (b) -62 from 0
(c) 2 from -7 (d) -340 from -370
2. Subtract -5 from 7. Subtract 7 from -5. Are the two results same?
3. From the sum of -38 and -12 subtract -18.

4. Subtract the sum of -8 and -28 from the sum of -13 and 31.
5. Simplify:
(a) - + -8 ( 6) + -11( ) (b) -12 18 15 3
+
-
+
(c) - - - -6 8 ( 15) (d) 7 - -( 9 + -) ( 3)
6. A place is 37 m above sea level and another is 35 m below sea level. What is the differ ence of
levels between the two places?
7. p and q are two integers such that p is the predecessor of q. Find the value of p q- .

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