Your blog category
(1) 539.712 cm2 (2) 538.721 em2 (3) 540.712 em2 (4) 539.217 cm2 Solution: Area of paper=Area of square +Area of equilateral triangle =1/2 (diagonal)2+ √3/4*(side)2 =1/2*32*32+√3/4*8*8 = 512 + 16 * 1.732 = 512 + 27.712 = 539.712 cm2 (Note: Diagonal of a square =√2 side) Then the option is (1) 539.712 cm2
(1) 25 (2) 30 (3) 35 (4) 20 Solution: Let the number of students be n. So, each of n students got 2n chocolates Total no. of chocolates = (2n)*n = 800 ⇒ 2n2 =800 ⇒ n2=400 ⇒ n=20 Then the option is (4)
(1) 20 (2)30 (3)40 (4)50 Solution: Let the original number of boys and girls be x and y respectively. Then x/y-15=2/1 ⇒ x = 2y – 30 ……….(i) Again, x-45/y-15=1/5 ⇒ 5x-225=y-15 ⇒ 5x= y-15+225 ⇒ 5(2y-30) = y+210 [From equation (i)) ⇒ 10y-150=y+210 ⇒ 10y-y=210+150 ⇒ 9y = 360 ⇒ y=360/9 = 40
Solution Scale of map = Size drawnActual size= 10cm1000cm (because 10 m = 1000 cm)= 1100Thus, the scale is 1:100.
Solution L = 2B – 1, Diagonal = 17. D² = L²+ B²⇒ 289 = (2B –1)² + B²⇒ B = 8 & L = 15.Also 8, 15, 17 is a Pythagorean triplet.So answer can be reached directly.
Solution Given: 5x²−2 , x=3We need to find the value of 5x²−2 at x=3We will put 3 in place of x in the expression 5x²−2Therefore, the value of the expression will be5x²−2=5(3)²−2=5(3)−2=45−2=43
The value of expression 5x²−2 when x=3 is (a)-12 (b) 8 (c) 43(d) 36 Read More »
Solution We haveNumber of faces F = 10Number of edges E = 20and number of vertices V = 15Euler’s formula:V + F – E = 2⇒ 15 + 10 – 20 = 2⇒ 5 ≠ 2Hence, it is not possible to have a polyhedron satisfying the above data
Verify whether a polyhedron can have 10 faces, 20 edges and 15 vertices. Read More »
Solution Let us say, the two consecutive positive integers be x and x + 1.Therefore, as per the given statement,x² + (x + 1)² = 365⇒ x² + x² + 1 + 2x = 365⇒ 2x² + 2x – 364 = 0⇒ x² + x – 182 = 0⇒ x² + 14x – 13x –
Find two consecutive positive integers, the sum of whose squares is 365. Read More »
Solution Given that the scale on the map is 1 mm: 6 mTo find the distance drawn on the map for an actual distance of 60 m,Scale of map = distance drawnActual distance1 = distance drawn6 60 mdistance drawn = 1 x 60 = 10 mm6Thus, the distance on the map for the actual distance
Solution Let us suppose Mohan rao will have to read x pages every day to finish the book in 8 days.As the number of days decreases, the number of pages increases.So, the number of days and number of pages are in inverse proportion.∴ 10 × 40 = 8 × xx=400/8⇒ x = 50 pagesHence, Mohan
