Question

une bouteille contient 4,2 l d’huile à lampe
a) combien de fois peut - on remplir une lampe
à l’huile dont le réservoir a une capacité
de 0,4 l ?
réponse :

Explanation:

Step1: Identify the operation

We need to find how many times a 0.4 L lamp can be filled with a 4.2 L bottle of oil. This is a division problem: total volume divided by volume per fill. So we calculate $4.2 \div 0.4$.

Step2: Perform the division

To divide decimals, we can multiply numerator and denominator by 10 to eliminate decimals: $\frac{4.2\times10}{0.4\times10}=\frac{42}{4}$. Then, $42\div4 = 10.5$. Wait, but the handwritten answer is 10? Wait, maybe a rounding or misinterpretation? Wait, no, let's check again. Wait, 0.4 L per lamp, 4.2 L total. $4.2 \div 0.4 = 10.5$. But maybe the question is about full fills? But the original problem's handwritten answer is 10? Wait, no, maybe I miscalculated. Wait, 0.4 10 = 4.0, and 4.2 - 4.0 = 0.2, so 10 full fills, but the problem says "combien de fois peut - on remplir" (how many times can we fill), maybe including partial? Wait, the handwritten answer is 10.5? Wait, the image has 42 written, maybe a miscalculation step. Wait, 4.2 / 0.4 = (4.2 10)/(0.4 10)=42/4 = 10.5. But the handwritten 42 might be a step. Wait, maybe the problem is in liters, and we do 4.2 / 0.4. Let's do it as 4.2 ÷ 0.4. 0.4 10 = 4.0, 4.2 - 4.0 = 0.2, so 10 times with 0.2 L left, but if we consider exact division, it's 10.5. But the handwritten answer is 10? Wait, maybe the question was 4 L? No, the problem says 4.2 L. Wait, maybe the original problem had 4 L? No, the text says 4,2 L. Anyway, following the calculation: 4.2 ÷ 0.4 = 10.5. But the handwritten 42 is from multiplying by 10. So 42 ÷ 4 = 10.5.

Answer:

10.5 (or 10 if considering full fills, but mathematically it's 10.5)