Beng, Chandra and Danial have some stickers. Chandra and Danial have 7/10 of the stickers. Beng and Danial have 6/7 of the stickers. Beng and Chandra have a total of 620 stickers. How many more stickers did Danial collect than Beng?
I'm just doing this one to see if I can solve it without "cheating" and looking at other's answers.....!!!
Let N be the total number of stamps....so we have
C + D = 49/70N (1)
B + D = 60/70N (2)
B + C = 620
Adding (1) and(2), we have
620 + 2D = (109/70)N → D = (109/140)N - 310
So
B + C + D = N
620 + (109/140)N - 310 = N
310 = (31/140)N → N = 1400
So D has (109/140)(1400) - 310 = 780
And B has
780 + = (6/7)(1400) → D = 1200 - 780 = 420
So D - B = 780 - 420 = 360 more
Beng and Danial have 6/7 of the stickers ,so chandra have 1/7 of the total stickers
so Danial have 7/10-1/7=39/70 of the total stickers , so beng have 6/7-39/70=21/70=3/10
Beng and chandra have 1/7+3/10=31/70,so the Danial ,Beng and chandra have 620/31*70=1400
Danial collect more 1400*(39/70-3/10)=1400*(9/70)=180 stickers than Beng
I think we need an adjudicator on this one - I don't have time at present
Thank you :))
i made a mistook.
39/70-3/10=39/70-21/70=18/70
(18/70)*1400=360 ,so Danial collect more 360 than Beng.
i am so sorry guys.
Beng, Chandra and Danial have some stickers. Chandra and Danial have 7/10 of the stickers. Beng and Danial have 6/7 of the stickers. Beng and Chandra have a total of 620 stickers. How many more stickers did Danial collect than Beng
$$\small{\text{
All Stickers $=x$
}}\\\\
\begin{array}{lcccc}
(1) & b+c+d=x & \quad c+d=x-b &\quad b+d=x-c &\quad b+c=x-d\\\\
\hline \\
(2) & c+d = \frac{7}{10}x &\frac{7}{10}x = x-b \\\\
(3) & b+d = \frac{6}{7}x & &\frac{6}{7}x = x-c \\\\
(4) & b+c = 620 & && 620 = x-d \\\\
\hline \\
& b+c+d=x & b=\frac{3}{10}x & c=\frac{1}{7}x & d=x-620\\\\
\end{array}\\
\begin{array}{rrcl}
& \frac{3}{10}x + \frac{1}{7}x + x-620 &=& x\\ \\
& x &=& 1400
\end{array}$$
$$\\b=\frac{3}{10}*1400 = 420\\\\
c=\frac{1}{7}*1400 = 200\\\\
d=1400-620 = 780\\\\
d-b=780-420 = 360$$
How many more stickers did Danial collect than Beng? 360
I'm just doing this one to see if I can solve it without "cheating" and looking at other's answers.....!!!
Let N be the total number of stamps....so we have
C + D = 49/70N (1)
B + D = 60/70N (2)
B + C = 620
Adding (1) and(2), we have
620 + 2D = (109/70)N → D = (109/140)N - 310
So
B + C + D = N
620 + (109/140)N - 310 = N
310 = (31/140)N → N = 1400
So D has (109/140)(1400) - 310 = 780
And B has
780 + = (6/7)(1400) → D = 1200 - 780 = 420
So D - B = 780 - 420 = 360 more