हिंदी
सी.आई.एस.सी.ई.आईसीएसई ICSE Class 7

21 – 3 ( B-7 ) = B+ 20 - Mathematics

Advertisements
Advertisements

प्रश्न

21 – 3 (b - 7) = b+ 20

योग

उत्तर

21 – 3 (b - 7) = b+ 20

⇒ 21 - 3b + 21 = b + 20 

⇒ - 3b + 42 = b + 20

⇒ - 3b - b = 20 - 42

⇒ - 4b = - 22

⇒ b = `(-22)/(-4) = 11/2`

∴ b = `11/2 = 5 1/2`

shaalaa.com
Simple Linear Equations in One Variable
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 12: Simple Linear Equations (Including Word Problems) - Exercise 12 (B)

APPEARS IN

सेलिना Concise Mathematics [English] Class 7 ICSE
अध्याय 12 Simple Linear Equations (Including Word Problems)
Exercise 12 (B) | Q 19

संबंधित प्रश्न

Solve the following equation:

3(b - 4) = 2(4 - b)


Solve the following equation:

`("2x" - 13)/5 - ("x" - 3)/11 = ("x" - 9)/5 + 1`


8y – 4y = 20


4x – 5x + 2x = 28 + 3x


9 (a+ 5) + 2 = 11


The difference between a number and one- fourth of itself is 24, find the number.


The numerator of a fraction is four less than its denominator. If 1 is added to both, is numerator and denominator, the fraction becomes `1/2` Find the fraction.


Solve the following equations for the unknown: (a + 2)(2a +5) = 2(a + 1)2 + 13


Solve the following equations for the unknown: `(1)/(2)(y - 1/3) + (1)/(4)(2y + 1/5) = (3)/(4)(y - 1/12)`


If `(2)/"m" xx 1(1)/(5) = (3)/(7) "of"  2(1)/(2)`, find the value of 'm'.


Solve the following equations: a(2x - b) - b(3x - a)+a(x + 1) = b(x + 5)


Two complementary angles differ by 14°. Find the angles.


Two planes start from a city and fly in opposite directions, one averaging a speed of 40 km/h more than that of the other. If they are 3400km apart after 5 hours, find their average speeds.


In an isosceles triangle, each of the two equal sides is 4 cm more than the base. If the perimeter of the triangle is 29 cm, find the sides of the triangle.


What number decreased by 12% of itself gives 1584?


There are certain benches in a classroom. If 4 students sit on each bench, 3 benches are left vacant; and if 3 students sit on each bench, 3 students are left standing. What is the total number of students in the class?


What number decreased by 18% of itself gives 1599?


In a factory a worker is paid Rs 20 per hour for normal work and double the rate for overtime work. If he worked for 56 hours in a week, find the number of hours of his normal work if he receives Rs 1440 in all.


In a factory male workers are paid one and a half times more than their female counterparts for each hour of work. In a particular week a husband and wife team worked for a total of 60 hours with the husband working twice as much as his wife. The total amount earned by both is Rs 960. If the husband's earning is 4 times that of his wife, find the number of hours each worked.


In a class there are a certain number of seats. If each student occupies one seat, 9 students remain standing and if 2 students occupy one seat, 7 seats are left empty. Find the number of seats in the class.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×