f(x) = -1, for all x>0. If f(a) = -1 and f(ab) = -1 then b =?

১

The price of a certain television set is discounted by 10 percent, and the reduced price is then discounted by 10 percent. The series of successive discount is equivalent to a single discount of -

20%

19%

18%

11%

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

19%

২

If u> t, r> q , s>t, t>r, which of the following must be true?

I only

II only

III only

II and III only

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

II and III only

সমাধান

u>t, t>r, r>q so, u> t>r>q s>t, t>r, r>q so, s>t>r>q

৩

A pen was sold at 15% loss. If the selling price was Tk. 8 more, than the seller could have made a profit of 10%. What was the purchase price of pen?

None of them

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

সমাধান

Let, Purchase price = Tk.x At 15% loss SP = Tk.(17x/20) At 10% profit SP = Tk.(11x/10) As per question , (17x/20) + 8 = (11x/10) Or, 5x = 160 Or, x = 32 Therefore, the required value = Tk.32

৪

Ms. Lyla wants to put up fencing around three sides of her rectangular garden and have a side of 20 meter unfenced. If the yard has an area of 680 square meters, how many yards of fencing does she need?

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

সমাধান

Length of the garden = 680/20 = 34 meter Total length of the three sides = 2×34 + 20 = 68 + 20 = 88 meter

৫

The difference between two numbers is 7 and their product is 60, then one of the two numbers must be -

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

সমাধান

x - y = 7; x = (y + 7) xy = 60 or , (y + 7).y = 60 or, y² + 7y - 60 = 0 or, (y + 12) (y – 5) = 0 So, Y = - 12,5 So, the two number is 12 and 5

৬

If the diameter of a circle is doubled the area will be -

4 Times

3 Times

2 Times

No increase

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

4 Times

সমাধান

Area of a circle is propotional to the square of the diameter. So, if the diameter of a square is doubled, its area will be quadrupled or 4 times.

৭

In a sugar-water solution, the ratio of water to sugar is 8:3. If you add 2 Kgs of sugar, the ratio become 2:1. What was the amount of sugar in the original solution?

4.5

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

সমাধান

W : S = 8 : 3 W/S = 8/3 3W = 8S Again, W/(s + 2) = 2/1 1W = 2s + 4 3W = 6S + 12 8S = 6S + 12 S = 6

৮

If the area of rectangle R with length 4 feet is equal to the area of square S, which has a perimeter of 24 feet , then the perimeter of rectangle R equals -

9 Feet

16 Feet

24 Feet

26 Feet

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

26 Feet

সমাধান

Side of the square S = 24/4 = 6 Area of the rectangle R = Area of the square S = 62 = 36 So, length of the rectangle R = 36 / 4 = 9 Therefore, perimeter of the rectangle R = 2(9 + 4) = 26 feet

৯

What percent of 25 is 0.20?

0.8

0.08

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

0.8

সমাধান

let x% of 25 is 0.2 so, (x/100) × 25 = 0.2 so, x = 0.8

১০

If N and P are both odd numbers, which of the following numbers must be an even number?

N+P

NP+2

N+P+1

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

N+P

অনুসন্ধান করুন

বিস্তারিত সমাধান

f(x) = -1, for all x>0. If f(a) = -1 and f(ab) = -1 then b =?

The price of a certain television set is discounted by 10 percent, and the reduced price is then discounted by 10 percent. The series of successive discount is equivalent to a single discount of -

If u> t, r> q , s>t, t>r, which of the following must be true?

A pen was sold at 15% loss. If the selling price was Tk. 8 more, than the seller could have made a profit of 10%. What was the purchase price of pen?

Ms. Lyla wants to put up fencing around three sides of her rectangular garden and have a side of 20 meter unfenced. If the yard has an area of 680 square meters, how many yards of fencing does she need?

The difference between two numbers is 7 and their product is 60, then one of the two numbers must be -

If the diameter of a circle is doubled the area will be -

In a sugar-water solution, the ratio of water to sugar is 8:3. If you add 2 Kgs of sugar, the ratio become 2:1. What was the amount of sugar in the original solution?

If the area of rectangle R with length 4 feet is equal to the area of square S, which has a perimeter of 24 feet , then the perimeter of rectangle R equals -

What percent of 25 is 0.20?

If N and P are both odd numbers, which of the following numbers must be an even number?

কোর্স

অনুসন্ধান করুন

বিস্তারিত সমাধান

f(x) = -1, for all x>0. If f(a) = -1 and f(ab) = -1 then b =?

সম্পর্কিত বিষয় সমূহ

সম্পর্কিত অন্যান্য প্রশ্ন

The price of a certain television set is discounted by 10 percent, and the reduced price is then discounted by 10 percent. The series of successive discount is equivalent to a single discount of -

If u> t, r> q , s>t, t>r, which of the following must be true?

A pen was sold at 15% loss. If the selling price was Tk. 8 more, than the seller could have made a profit of 10%. What was the purchase price of pen?

Ms. Lyla wants to put up fencing around three sides of her rectangular garden and have a side of 20 meter unfenced. If the yard has an area of 680 square meters, how many yards of fencing does she need?

The difference between two numbers is 7 and their product is 60, then one of the two numbers must be -

If the diameter of a circle is doubled the area will be -

In a sugar-water solution, the ratio of water to sugar is 8:3. If you add 2 Kgs of sugar, the ratio become 2:1. What was the amount of sugar in the original solution?

If the area of rectangle R with length 4 feet is equal to the area of square S, which has a perimeter of 24 feet , then the perimeter of rectangle R equals -

What percent of 25 is 0.20?

If N and P are both odd numbers, which of the following numbers must be an even number?