151. Let
the number of pineapples and watermelons be X and y respectively.
Then, 7X + 5y = 38 or 5y =
(38 – 7x ) or y = 38 – 7x / 5.
Clearly, y is a whole number,
only when ( 38 -7x ) is divisible by 5. Then
happens when X = 4.
152. Let
number of boys = X. then, number of girls = 5x.
Total
number of children = ( X + 5X ) = 6x.
Thus,
the total number of children must be a multiple of 6.
153. Let
F and C denote the temperatures in Fahrenheit and Celsius respectively.
Then,
F – 32 / 212 – 32 = c – 0/ 100 – 9 F –
32 /180 = C/ 100.
If c
= 35, then F = ( 35 / 100 x 180 ) + 32 = 63 + 32 = 95.
154. Let
D’s share =Rs. X. then, C’s share = Rs. X.
B’s
share = Rs. (X + 125).A’s share = Rs. (x + X+ 125) = Rs. (2X + 125)
(2X + 125 ) +( X + 125) +X + x = 750 5x = 5000 x = 100.
Hence,
A’s share = 2X + 125 = Rs. ( 2 x 100 + 125) = Rs. 325.
155. Let
Gagan’s share = Rs. X.
Then,
Sachin’s share = Rs. (X/5) and Rohit’s share =Rs. (2X/ 5)
2X /
5 + x/5 + X = 1000 8X = 5000 X = 625.
156. Total
number od digits = (No. of digits in 1-
digits in 3-digit page nos.)
= ( 1 x 9 + 2 x 90 + 3 x 267) = (9 + 180 + 801) =
990.
157. No.
of digits in 1 – digit page nos. = 1 x 9 = 9.
No.
of digits in 2- digit page nos. = 2 x 90 = 180.
No.
of digits in 3 – digit page nos. = 3 x 900 = 2700.
NO. of digits in 4 – digit page nos. = 3189 –
(9 + 180 + 2700) = 3189 – 2889 = 300.
No.
of pages with 4 – digit page nos. = (300 / 4) = 75.
Hence,
total number of pages = 999+ 75) = 1074.
158. Each
row contains 12 plants.
Leaving 2 corner plants, 10 plants, in between have
(10 x 2) metres and 1 metre on each side is left.
Length = (20 + 2 ) m = 22 m.
159. Required
fraction = 11 sec / 1hr. = 1 sec. / (a x 60 x 60 ( sec. = 1/3600
160. Height
at the third bounce = [32 x (3/4)³] m = (32 x 27 / 64) m = 27 / 2 m = 13
1/2 m.
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