Are the bonds in each of the following substances ionic, nonpolar covalent, or polar covalent? Arrange the substances with polar covalent bonds in order of increasing bond polarity:


1

99

May 29, 2020

Factorise: 250(ab)^3+2


2

104

June 19, 2019

Prove (a+b+c)^3  a^3  b^3  c^3 = 3(a+b) (b+c) (c+a)


2

75

June 19, 2019

If a+b+c = 0, then prove that (b+c)^2 / 3bc + (c+a)^2 / 3ca + (a+b)^2 / 3ab = 1


2

355

June 18, 2019

If a+b = 12 and ab= 27, find the value of a^3+b^3


2

95

June 18, 2019

If A,B,C are all non zero and A+B+C = 0 Prove that A2/BC + B2/CA + C2/AB = 3


2

161

June 18, 2019

Prove that (a+b+c)3 –a^3b^3c63= 3(a+b)(b+c)(c+a)


2

137

June 18, 2019

Factorise: x^3 + 13x^2 + 32x + 20


2

62

June 18, 2019

Represent root 5 on number line


2

279

June 18, 2019

If a+b+c=5,and ab+bc+ca=10,prove a^3+b^3+c^33abc=25


2

255

June 17, 2019

Prove that (a+b+c)whole cube  a cube b cube  c cube = 3(a+b)(b+c)(c+a )


2

1881

June 17, 2019

The blood groups of 30 students of class VIII are recorded


2

152

April 12, 2019

Eleven bags of wheat flour, each marked 5 kg, actually contained the following weights of flour


2

192

April 12, 2019

Activity : Ask all the students in your class to write a 3digit number


2

313

April 10, 2019

Activity: Note the frequency of twowheelers, threewheelers and fourwheelers going past


2

329

April 10, 2019

The distance (in km) of 40 engineers from their residence to their place of work were found


2

91

April 10, 2019

To know the opinion of the students about the subject statistics, a survey of 200 students


2

136

April 10, 2019

A teacher wanted to analyse the performance of two sections of students in a mathematics test


2

221

April 10, 2019

An organisation selected 2400 families at random and surveyed them to determine


2

262

April 10, 2019

Three coins are tossed simultaneously 200 times with the following frequencies


2

381

April 10, 2019

In a particular section of class IX, 40 students were asked about the month of their birth


2

186

April 10, 2019

1500 families with 2 children were selected randomly, and the following data were recorded


2

342

April 10, 2019

In a cricket match, a batswoman hits a boundary 6 times out of 30 balls she plays


2

126

April 10, 2019

Give one example of a situation in which (i) the mean is an appropriate measure of central tendency


2

251

April 10, 2019

Find the mean salary of 60 workers of a factory from the following table


2

317

April 10, 2019

Find the mode of 14, 25,14, 28,18,17,18,14, 23, 22,14 and 18


2

264

April 10, 2019

The following observations have been arranged in ascending order


2

239

April 10, 2019

In a mathematics test given to 15 students, the following marks (out of 100) are recorded


2

288

April 10, 2019

The following number of goals were scored by a team in a series of 10 matches


2

325

April 10, 2019

100 surnames were randomly picked up from a local telephone directory and a frequency


2

240

April 10, 2019
