বর্তমানে মাথাপিছু আয় ১ হাজার ৪৬৫ মার্কিন ডলার। According to Bangladesh Bureau of Statistics.---Updated: 24 Nov. 2016

1 faster person = 2 slower person so , 2 faster +one slower = 5 slower person 5 slower person can do the work in 12 days 1   ,,         ,,                       ,,   ,,                    12X5 days= 60 day as, 2 slower = 1 faster then , 1 faster person can do the work in 60/2 = 30 days

suppose the fraction is x/y

if, x+1/y+1 = 4 or,y=(x-3)/4 again, x-1/y-1=7 or, y=(x+6)/7 or, (x-3)/4=(x+6)/7 or, x=15  

Dealer এর cost  x টাকা হলে , in 20% profit , price =(x+x X 20/100)=x+x/5= 6x/5 when cost  6x/5 then if profit 30% then cost  =6x/5+( 6x/5 X 30/100)= 6x/5+18X/50 here, 6x/5+6x+5+18X/50=312 or, x = 200

প্রথম টুকরা x , ২য় টুকরা ২x, ৩য় টুকরা 4x শর্ত মতে , x+2x+4x=105 then, 7x= 105 x=15 মধ্য টুকরা = 15 x 2 = 60  

s+10 = j.......(i) 2(s+5)=j+5 or,j=2s+10-5....(ii) comparing i and ii s+10=2s+5 or, s=5 after 3 years, sohans age =5+3=8  

7th  number = 31 6th          “     = 35 5th   number = 39 4th   number = 43

লাভ ও ক্ষতি সমপরিমাণ বলে , ক্রয়মূল্য = 1920+1280/2= 1600 tk 25% লাভে  বিক্রয়মুল্য= 1600 +1600 x    25/100 = 2000  tk  

14(4x)2/(16x+1-2x+18x)

= 14 X (22x)2/24x+4-2x+1+3x =14 x 24x/24x.24-24x.2 =14x24x/24x(16-2) =14x24x/14x24x =1

√x + (1/√x) = 3 or, (√x + 1/√x)2=9 or, x+ 1/x +2=9 or,x+1/x=7 or(x+1/x)2=49 or,x2 + 1/x2 + 2 = 49 or, x2 +1/x2 = 47 or, (x2+1/x2)2=(47)2 or,x4+1/x4+2=2209 or, x4+1/x4 =2209-2=2207

y=6x or,6y=6.6x or, 6y= 6x+1

-1-3x≥14

or, -3x≥15

or, 3x≤-15 or, x≤-5

if, x=y   1-3t=2t-1  or,t=2/5

here, a+b=15-----(i)            a-b =1------(ii) i+ii→ 2a=16         or, a=8 i-ii →2b=14         or, b=7 so, ab= 7 x 8 =56  

x+y=8z or, x+y+z=8z+z or, x+y+z=9z then average = 9z/3 = 3z

 larger sphere  এর আয়তন = 4/2 π (9)3= 972π ঘন সেমি 108 কেজি এর আয়তন  972π   ঘন সেমি 1        ”                “       “                 972π/108 “      “  32  “               “            “                 972π x 32 /108 “    “                           &

if , radius = r then here, 2πr-2r=60                   or, r = 60/(2π-2)                   or,r= 14.008  

অপর বাহু= b তাহলে , 2(a+b)=l or, a+b=l/2 or, b=1/2-a or, b=l-2a/2 ক্ষেত্রফল = (l-2a/2)  X a = (la-2a2)  /2