Selina solutions

# Question 1

Q1) Check whether the following quantities form a proportion or not?

(i) 3x,7x,24 and 56

(ii) 0.8,3,2.4 and 9

(iii) 1\frac{1}{2},3\frac{1}{4},4\frac{1}{2}\ and\ 9\frac{3}{4}

(iv) 0.4, 0.5, 2.9 and 3.5

(v)2\frac{1}{2},5\frac{1}{2},3.0\ and\ 6.0

Solution:

(i) if 3x, 7x, 24 and 56 are in proportion

Then

3x\times56=7x\times24

168x = 168 x

LHS=RHS

(ii) if 0.8,3,2.4and 9 are in proportion

Then

0.8\times9=2.4\times3

7.2=7.2

LHS = RHS

(iii) if 1\frac{1}{2},3\frac{1}{4},4\frac{1}{2}\ and\ 9\frac{3}{4} are in proportion

Then

1\ \frac{1}{2}\times9\ \frac{3}{4}=3\ \frac{1}{4}\times4\ \frac{1}{2}

=\frac{3}{2}\times\frac{39}{4}=\frac{15}{4}\times\frac{9}{2}

\frac{117}{8}=\frac{117}{8}

LHS=RHS

(iv)If 0.4, 0.5, 2.9 and 3.5 are in proportion

Then

0.4\times3.5=0.5\times2.9

1.40 = 1.40

LHS=RHS

(v) if 2\frac{1}{2},5\frac{1}{2},3.0\ and\ 6.0 are in proportion

Then

\frac{5}{2}\times6.0=\frac{11}{2}\times3.0

\frac{30}{2}=\frac{30}{2}

LHS=RHS

Want to top your mathematics exam ?

Learn from an expert tutor.

Lido

Courses

Race To Space

Teachers

Syllabus

Maths | ICSE Maths | CBSE
Science | ICSE Science | CBSE
English | ICSE English | CBSE

Terms & Policies

NCERT Syllabus

Maths
Science

Selina Syllabus

Maths
Physics
Biology

Allied Syllabus

Chemistry