Question

An expression is shown.

​

​ 2.1×105 + 4.3×104

​

​Which expression is equivalent?


A

2.53×104

B

2.53×105

C

6.4×105

D

6.4×109

Answer 1

25.3 ×
`10^(4)` is the equivalent expression

Explanation:

In this question, we are asked to select from the options the expression that is equivalent to the written expression.

2.1 ×
`10^(5)` + 4.3 *
`10^(4)`

Now, we can factor out
`10^(4)`.

This gives;

`10^(4)`{[2.1 × 10] + 4.3}

`10^(4)`( 21 + 4.3)

=
`10^(4)` × 25.3