2. Little John claims he is $2 \mathrm{~m} 8 \mathrm{~cm}$ and $3 \mathrm{~mm}$ tall.
What is this height in metres?
A $2.83 \mathrm{~m}$
B $2.803 \mathrm{~m}$
C $2.083 \mathrm{~m}$
D $2.0803 \mathrm{~m}$
E $2.0083 \mathrm{~m}$
Solution
C One metre is 100 centimetres. So $1 \mathrm{~cm}=0.01 \mathrm{~m}$ and $8 \mathrm{~cm}=0.08 \mathrm{~m}$. Similarly, one metre is 1000 millimetres. So $1 \mathrm{~mm}=0.001 \mathrm{~m}$ and $3 \mathrm{~mm}=0.003 \mathrm{~m}$. Therefore Little John's height is $2 \mathrm{~m}+0.08 \mathrm{~m}+0.003 \mathrm{~m}=2.083 \mathrm{~m}$.