Advertisements
Advertisements
Question
Evaluate: 20.8 × 19.2
Sum
Advertisements
Solution
20.8 × 19.2
= (20 + 0.8) (20 − 0.8)
= (20)2 − (0.8)2 ......[ ∵ (a − b) (a + b) = a2 − b2]
= 400 − 0.64
= 399.36
shaalaa.com
Is there an error in this question or solution?
APPEARS IN
RELATED QUESTIONS
Simplify the following
`(7.83 + 7.83 - 1.17 xx 1.17)/6.66`
If `x^2 + 1/x^2 = 66`, find the value of `x - 1/x`
If a + b + c = 0, then write the value of \[\frac{a^2}{bc} + \frac{b^2}{ca} + \frac{c^2}{ab}\]
Use the direct method to evaluate the following products :
(y + 5)(y – 3)
Evaluate: (2a + 0.5) (7a − 0.3)
Expand the following:
(x - 3y - 2z)2
Simplify by using formula :
(2x + 3y) (2x - 3y)
If `x^2 + (1)/x^2 = 18`; find : `x - (1)/x`
Evaluate the following :
7.16 x 7.16 + 2.16 x 7.16 + 2.16 x 2.16
Give possible expressions for the length and breadth of the rectangle whose area is given by 4a2 + 4a – 3.
