Question

A boy drinks 200 ml of milk everday while his sister drinks 0.15 L milk everday. How many millilitres of milk do they drink in a week?

• A. 2400 millilitres
• B. 2500 millilitres
• C. 2450 millilitres
• D. 2650 millilitres

Answer 1

The correct option is C 2450 millilitres

The boy drinks 200 millilitres of milk in a day.
And, his sister drinks 0.15 litres.
$\because 1l=1000mL\therefore 0.150l=0.150\times 1000mL\text{Shifting the decimal point to three places to the right}\Rightarrow 0.150l=150mL$

So, millilitres of milk they combinedly drink per day = 200 + 150 = 350 millilitres.
1 week = 7 days
$\therefore$ The number of millilitres of milk they will drink in a week is 350 × 7 mL = 2450 mL.