Question

If one gold bangle is made from 12 gram 250 milligrams of gold, how much gold will be needed to make 8 bangles? $\left( 1000mg=1g \right)$ .

Answer 1

Hint: First, we will convert the quantity given as 12 gram 250 milligrams into a single unit of milligram using the relation $1000mg=1g$ . Then using the unitary method, we will find out the total quantity of gold needed for 8 bangles. After getting this, we will again convert this into grams units from milligram using the same conversion i.e. $1000mg=1g$ . Thus, we get the answer.

Complete step by step answer:
Here, in the question we are given the quantity of gold needed to make one bangle i.e. 12 gram 250 milligrams. So, we will convert this into milligrams using the relation given to us i.e. $1000mg=1g$.
So, we will convert 12 grams to milligrams by applying unitary method given as below:
$\begin{align}
  & 1g=1000mg \\
 & 12g=? \\
\end{align}$
On simplifying, we get
$=12\times 1000=12000mg$
Now, we have total quantity of gold in milligrams is
$12000+250=12250mg$
Now, it can be said that for one bangle 12250mg of gold is needed then for 8 bangles mow much gold is needed. So, applying unitary method to solve this we get as:
$\begin{align}
  & 1bangle=12250mg \\
 & 8bangle=? \\
\end{align}$
On further solving, we get
$=8\times 12250=98000mg$
Thus, 98000mg of gold is needed to make 8bangles.
Again, we will convert milligram to gram using the same conversion we used earlier i.e. $1000mg=1g$ . So, we will get
$\begin{align}
  & 1000mg=1g \\
 & 98000mg=? \\
\end{align}$
On solving, we get as
$=\dfrac{98000}{1000}=98gram$
Thus, a total 98 grams of gold is needed for 8 bangles.

Note: It is not necessary to convert into milligrams and then to grams at the end. We can directly convert into grams from the beginning and can get the same answer. We are given 12 gram 250 milligrams which on converting into grams get as
$\begin{align}
  & 1000mg=1g \\
 & 250mg=? \\
\end{align}$
On solving, we get
$\dfrac{250}{1000}=0.25g$
So, the total quantity for one bangle is $12+0.25=12.25g$ gold.
Now, using unitary method we get quantity of gold needed to make 8 bangles as
$12.25\times 8=98.00g$
So, by this also we get the same answer.