Let, their investments are = x, y & z
∴The first partner's investment will be 14x Tk.
Second partner's investment will be 8y Tk.
Third partner's investment will be 7z Tk.
So we get from above information, 14x8y=57
=7x4y=57 =xy=2049 ∴x : y = 20 : 49 Again, 8y7z=78 =yz=4964 ∴y : z = 49 : 64 ∴x : y : x = 20 : 49 : 64
Two pipes A and B can fill a tank in 20 hours and 30 hours respectively. Both the pipes are opened to fill the tank but when the tank is 13 full, a leak develops in the tank through which 13 water supplied by both the pipes goes out. How much time will the tank take to be full?
In 1 hour, A and B together can fill = 120+130=3+260=560=112 part of the tank ∴Before laekage, both pipe would take to fill 13 part of the tank =13112=13×121=4 hours Now, in 1 hour, both pipes can fill up the tank effectively = 112×23=118part Remainting (1-13) =23 part of the tank will take = 23118=23×181=12 hours ∴Total time required = 4+12=16 hours (ans.)
Let, principal amount of x; and rate of compound interest be r; time, n= ? apply the law of compound interest , we can write x(1+r100)3=8x =(1+r100)3=8xx=8 ∴(1+r100)3=8....................(i) Now, according to question, x (1+r100)n=16x =(1+r100)n=16 =(1+r100)n=24 =(1+r100)=2(3×43) =(1+r100)n=843 ={(1+r100)3}n33}43 =n3 =43 ∴n=4
After 100 days, remaining work = (1-2.515)=(1-16)=6-16=56 part of work Remaining days = 300-100=200 days Now, 16 part of work is done in 100 days by 45 men ∴56 part of work is done in 200 days by =45×100×6×5200×6=112.5=113 men ∴Number of extra men needed = 113-45 = 68 (ans.)
The bucket contained x liters of A and y liters of B Given that, xy=73 ∴x=7y5...........(i) and y = 5x7........(ii) sum of ratio = 5+7=12 Now, in 9 liters of replaced mixture, the amount of A was = 712×9=214 part and the amount of B was = 9-214=36-214=154 part According to question, x-214y-154+9=79 =x-2145x7+214=79 =9x-1894=5x+1474 =4x=1894+1474 =189+1474 =3364=84 ∴x=844=21