# Decimal Numbers Quiz Set 020

### Question 1

247887 is same as?

A

\$2.47887 × 10^{5}\$.

B

\$2.47887 × 10^{4}\$.

C

\$2.47887 × 10^{3}\$.

D

\$2.47887 × 10^{2}\$.

Soln.
Ans: a

### Question 2

What is x in \$0.008/x = 10\$?

A

0.0008.

B

0.008..

C

0.08..

D

0.00008..

Soln.
Ans: a

The expression becomes \$x = {8/1000} × {1/10}\$ = 0.0008.

### Question 3

What is \$9.102 - (-0.5) + 0.04 - (-0.02)\$?

A

9.662.

B

8.662.

C

7.662.

D

5.662.

Soln.
Ans: a

The given expression is same as \$9.102 + 0.5 + 0.04 + 0.02\$, then by simple addition we get \$9.102 + 0.5 + 0.04 + 0.02 = 9.662\$.

### Question 4

What is \${(-32) × 2.9 - 47 × (-3.8)}/6.9\$?

A

\$12{10/23}\$.

B

\$12{9/23}\$.

C

\$12{7/23}\$.

D

\$12{11/23}\$.

Soln.
Ans: a

Observe that all fractional numbers are having one digit to the right of the dot. So we can cancel all the dots and get a plain expression: \${(-32) × 29 - 47 × (-38)}/69\$. We can now simpilfy the minus signs to get \${(47 × 38) - (32 × 29)}/69\$ which equals \${286/23}\$, which is same as: \$12{10/23}\$

### Question 5

What is x in \$0.006/x = 0.1\$?

A

0.06.

B

0.6.

C

6.0.

D

0.006.

Soln.
Ans: a

The expression becomes \$x = {6/1000} × {10}\$ = 0.06.