211. Since ( x
– y) + ( y – z) (z – x) / (a² + b²+ c²-ab – b c – ca = a + b + c = (38 + 34 +
28) = 100.
Given exp. = (3 ( x – y )
*y – z) (z – x ) / 9 (x – y ) ( y –z ( z –x ) = 1/3.
212. Let total
score be X. then, highest score = 3 X / 11.
Remainder = (x – 3 x / 11 )
= 8 x / 11.next highest score = 3 / 11 of 8x / 11= 24 x/ 121.
3x /11 – 24x/ 121 = 9 33x – 24 x = 9x 121 9x = 9 x 121 x = 121.
213. X +
3X x 0.50 + 14 x 0.10 + 4X x 0.05 = 50.
X + 1.5X + 1.40 + 0.2 X =
50 2. 7 X = 48. 60 X = 18.
214. Suppose
their paths cross after x minutes.
Then, 11 + 57X = 51 –
63x 120 x = 40 x = 1/3.
Number of floors covered
by David in (1/3) min. = (1/3 x 57) = 19.
So, their paths cross at
(11 + 19) i.e. 30 th floor.
215. N x 50 =
(325000 – 300000) = 25000. N = 500.
216. Let total
number of children be x. then, X x 1/8 x = x/2 x 16 X = 64.
Number of notebooks =
1/8 x² = (1/8 64 x 64) = 512.
