A. 484Sq.cm
B. 538 2/7 Sq.cm
C. 616 Sq.cm
D. 644 Sq.cm
A. 70, 10 kmph
B. 35, 27 kmph
C. 50, 60 kmph
D. 45, 55 kmph
Explanation:
Speed of the boat in still water = (60+80)/2 = 70 kmph. Speed of the stream = (80-60)/2 = 10 kmph.
A. 420
B. 515
C. 435
D. 518
A. 295m2
B. 299m2
C. 300m2
D. 375m2
Explanation:
Area under the grass = [(25 x 15) – {(25 x 2)+ (15 x 2) – (2 x 2)}] Sq.m
= [375 –(50 +30 -4)]Sq.m =(375 – 76)Sq.m = 299 Sq.m
A. 9 %
B. 30 %
C. 60 %
D. 69 %
Explanation:
Let, side = 100cm.
Area = (100 × 100) cm2 = 10000 cm2
New area = (130 × 130) cm2 = 16900 cm2
Increase in area = (6900/10000 ×100) % = 69 %
A. 120
B. 260
C. 240
D. 220
Explanation with best method.
5 Steps
1.Data:
Train station platform= 36Sec
Standing platform = 20Sec
Speed of train = 54km/hr
2.Required:
Length of platform= x=???
3.Formula:
X+length of train/Train station platform
4.Solution: first for terms
Speed = 54 ×1000m/3600sec = 15 m/Sec.
Length of the train = (15 m/Sec × 20Sec = 300 m.
Let the length of the platform be x metres.
Now, x + 300m /36Sec= 15 m/Sec
x+300m= 15m/Sec×36Sec
x + 300m = 540m
x= 540m-300m
x = 240 m.
5.Result:
Length of platform=x=240m
A. 25 %
B. 50%
C. 75%
D. 100%