Question

krishna sold 10pens with profit % 20% for of total 500rupees find cp

Answer 1

let cp is 100%
then sp = 120% because profit = 20%
means 120% = 500
then 100% = ( 500/120)×100
1250/3 = 416.66
cp = 416.66Rs

Answer 2

(1) Distance travelled in first 5 sec= area of ABDE= 20×s=80m

(2) Distance travelled after the brakes are applied (area of BCD)=

2

1

×8×5=20m

(3) Total distance travelled= AreaofABCDE+AreaofBCD=80+20=100m

(4) Acceleration during the first 5 sec= 0, because uniform velocity.

(5) Acceleration during the last 8 sec= v=0,u=20m/s,t=8sec

⇒v=u+at⇒0=20+a(8)

⇒a=−2.5m/s

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