How much salt must we add to 10 grams of a 20% salt solution to strengthen it into a 50% solution?

১

If the product of three consecutive integers is 210, then the sum of the two smaller integers is -

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

উত্তর

সমাধান

Here, 210 = 2 x 3 x 5 x 7 Product of three consecutive integers 5, 6 & 7 = 5 x 6 x 7 = 210. So, the sum of the first two integers = 5 + 6 = 11

২

The diameter of a wheel is 63 cm. Distance traveled by the wheel in 100 revolutions is ----

99 meters

198 meters

63 meters

136 meters

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

198 meters

সমাধান

Radius of the wheel, R = 63/2 cm = 31.5 cm Distance travelled in one revolution = 2 π R = 2 π x (31.5) = 63 π cm = 0.63 π meters So, distance travelled in 100 revolutions = 100 x 0.63 π = 63 x 3.1416 = 198 meters

৩

A digital 12 hour clock falls behind 10 minutes each day. How many days will it take to reach a point where the clock will indicate the correct time?

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

সমাধান

it falls behind 10 mins each day so to show correct time it should lose 12 hours(720 mins) if it has only 12 hour divisions no. of days = 720/10 = 72 so in 72 days it would lose 720 mins or 12 hours after 72 days it would show the time correctly.

৪

Novera bought a ticket of a cricket match for TK. 25 and later sold the ticket to Nahid for TK. 75. What was the percent increase in the price of the ticket?

50%

100%

300%

200%

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

200%

সমাধান

Profit = (0.75 - 0.25) / 0.25 x 100% = 0.5 / 0.25 x 100% = 200%

৫

If the circumference of a circle is increased by 50%, its area will be increased by:

50%

100%

125%

225%

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

125%

সমাধান

Circumference of a circle increases only with radius. Therefore, radius of the circle gets increased by 50%. Now, new radius = R + 50% of R = 1.5R Initial area = π R2 New area = π (1.5R)2 = 2.25 π R2 Percent increase = ((2.25 π R2) - (π R2)} / (π R2) x 100% = 125%

৬

A manufacturer of jam wants to make a profit of Tk. 0.65 each to make first 100 jars of jams and Tk. 0.55 to make each jar after the first 100. How much profit he will make from 300 jars of jam?

Tk. 165

Tk. 175

Tk. 185

Tk. 220

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

Tk. 175

সমাধান

Profit from first 100 jars = 0.65×100 = 65 TK. Profit from the rest (300 - 100 = 200) jars = 0.55×200 = 110 TK Total profit = 65 + 110 = 175 TK

৭

A Company employs 15 persons, each works 44 hours a week. If 4 persons are absent, how many hours a week would the rest of the persons have to work to make up the time lost?

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

সমাধান

Total work hours per week = 44 x 15 = 660 Persons present = 15 - 4 = 11 Working hour per person = 660 / 11 = 60 hours per week.

৮

A man can row downstream at 10 kmph and upstream at 5 kmph. The man's rowing rate in still water is ----

2.5 km/hr

5 km/hr

7.5 km/hr

15 km/hr

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

7.5 km/hr

সমাধান

Let the man's rowing rate and stream's flowing rate be U and V respectively. So, U + V = 10 And, U - V = 5 - - - - - - - - - - - - - - - - - - - - - - - U + U = 10 + 5 [By addition] or, 2U = 15 So, U = 7.5 km/hr

৯

The ratio of the angles of a triangle is 2: 3: 4. What is the largest angle in degrees?

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

সমাধান

Let the angles be 2x, 3x and 4x respectively. Now, 2x + 3x + 4x = 180° or, 9x = 180° or, x = 180/9 = 20 So, the largest angle = 4x = 4 x 20 = 80°

১০

If 15 men can reap a field in 35 days, in how many days will 21 men reap the field?

49 days

9 days

25 days

29 days

উত্তর সিলেক্ট করলে সঠিক ও ভুল দেখাবে।

বিস্তারিত

উত্তর

25 days

সমাধান

15 men can reap the field in 35 days 1 man can reap the field in 35 x 15 days So, 21 men can reap the field in 35 x 15 / 21 = 25 days

অনুসন্ধান করুন

বিস্তারিত সমাধান

How much salt must we add to 10 grams of a 20% salt solution to strengthen it into a 50% solution?

If the product of three consecutive integers is 210, then the sum of the two smaller integers is -

The diameter of a wheel is 63 cm. Distance traveled by the wheel in 100 revolutions is ----

A digital 12 hour clock falls behind 10 minutes each day. How many days will it take to reach a point where the clock will indicate the correct time?

Novera bought a ticket of a cricket match for TK. 25 and later sold the ticket to Nahid for TK. 75. What was the percent increase in the price of the ticket?

If the circumference of a circle is increased by 50%, its area will be increased by:

A manufacturer of jam wants to make a profit of Tk. 0.65 each to make first 100 jars of jams and Tk. 0.55 to make each jar after the first 100. How much profit he will make from 300 jars of jam?

A Company employs 15 persons, each works 44 hours a week. If 4 persons are absent, how many hours a week would the rest of the persons have to work to make up the time lost?

A man can row downstream at 10 kmph and upstream at 5 kmph. The man's rowing rate in still water is ----

The ratio of the angles of a triangle is 2: 3: 4. What is the largest angle in degrees?

If 15 men can reap a field in 35 days, in how many days will 21 men reap the field?

কোর্স

অনুসন্ধান করুন

বিস্তারিত সমাধান

How much salt must we add to 10 grams of a 20% salt solution to strengthen it into a 50% solution?

সম্পর্কিত বিষয় সমূহ

সম্পর্কিত অন্যান্য প্রশ্ন

If the product of three consecutive integers is 210, then the sum of the two smaller integers is -

The diameter of a wheel is 63 cm. Distance traveled by the wheel in 100 revolutions is ----

A digital 12 hour clock falls behind 10 minutes each day. How many days will it take to reach a point where the clock will indicate the correct time?

Novera bought a ticket of a cricket match for TK. 25 and later sold the ticket to Nahid for TK. 75. What was the percent increase in the price of the ticket?

If the circumference of a circle is increased by 50%, its area will be increased by:

A manufacturer of jam wants to make a profit of Tk. 0.65 each to make first 100 jars of jams and Tk. 0.55 to make each jar after the first 100. How much profit he will make from 300 jars of jam?

A Company employs 15 persons, each works 44 hours a week. If 4 persons are absent, how many hours a week would the rest of the persons have to work to make up the time lost?

A man can row downstream at 10 kmph and upstream at 5 kmph. The man's rowing rate in still water is ----

The ratio of the angles of a triangle is 2: 3: 4. What is the largest angle in degrees?

If 15 men can reap a field in 35 days, in how many days will 21 men reap the field?