২২৭২১
what least number must be added to 1056 , so that the sum is completely divisible by 23?
উত্তর
3
সমাধান
23|1056|4595 - 136116 - 21
⸫ প্রয়োজনীয় least number = (23 - 21) = 2
২২৭২২
Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. what is the probability that the ticket drawn has a number which is a multiple of 3 or 5?
উত্তর
9/20
সমাধান
S = [1,2,3,4, - - - - - - 19,20]
ধরি, E = event of 3 অথবা 5 এর multiple পাবার সম্ভাব্যতা = [3,6,9,12,15,18,5,10,20]
⸫ P(E) = n(E)/n(S) = 9/20
২২৭২৩
If product of 3 consecutive integers is 120, then the sum of the integers is--
উত্তর
15
সমাধান
সহজ উপায় হচ্ছে Answer এ দেয়া Number গুলো observe কর
6x7x8 = 336;5x9x7 = 210 and 4x5x6 = 120; So, the sum of the integers is 4 + 5 + 6 = 15
২২৭২৪
There are 900 students in a school. 4% of them left the school and 50% of the remaining are girls. How many girls remained?
উত্তর
432
সমাধান
900 জন এর 4% = 900 x .04 = 36
36জন চলে যাওয়ায় বাকি থাকে = 900 - 36 = 864
এবং বাকি 864এর 50% girls = 864 x .50 = 432
২২৭২৫
The minimum value of 2x2 +8x -5 is
উত্তর
-13
সমাধান
2x2 + 8x - 5 = 2(x2 + 2.x.2 + 22) - 8 - 5 = 2(x + 2)2 - 13
যখন X + 2 = 0,তখন 2x2 + 8x - 5 এর value সবনিন্ম, যা - 13
২২৭২৬
There are 12 more apples than oranges in a basket of 36 apples and oranges. How many apples are in the basket?
উত্তর
24
সমাধান
Let, oranges = x and Apples = x + 12
So, x + (x + 12) = 36
or,2x = 24
So,x = 12
So, Apples = 12 + 12 = 24
২২৭২৭
Jesmin spent one-third of her money on books and half of the remaining money on clothing. She then spent three fourth of what she had left on food. She had Tk. 500 left over. How much money did she start with?
উত্তর
Tk. 6,000
সমাধান
Spent on books = 1/3
Spent on clothing = 1/2 of (1 - 1/3) = 1/2 × 2/3 = 1/3
Spent on food = 3/4 × { 1 - (1/3 + 1/3)} = 3/4 × (1 - 2/3) = 3/4 × 1/3 = 1/4
Left over = 1 - (1/3 + 1/3 + 1/4) = 1 - (4 + 4 + 3)/12 = 1 - 11/12 = 1/12
Now, 1/12 ≡ 500 TK
Then, she started with 500×12 = 6000 TK
২২৭২৮
Azman travels 20 kilometers towards north, then 30 kilometers towards east, and then 20 kilometers towards north. How many kilometers is he now from the starting point?
উত্তর
50
২২৭২৯
Of the fruit that arrives at a cannery, 20 percent by weight is rejected before processing. Of the fruit that is processed, 15 percent by weight is rejected be fore canning. Of the fruit that arrives at the cannery, what percent by weight is canned?
উত্তর
68%
সমাধান
Let the amount arrives be F.
Remaining before processing = F - 20% of F = 0.8F
Remaining after processing = 0.8F - 15% of 0.8F = 0.8F - 0.12F = 0.68F = 68% of F
So, amount of food canned = 68%
২২৭৩০
Farid can complete a job in 12 hours, and Jibon can complete the same job in 8 hours. Farid starts the job at 9 am and stops working at 3 pm. If Jibon starts working at 4 pm to complete the remaining job, at what time is the job finished?
উত্তর
8 p.m.