Gcse maths question help!

You will first need to find the volume of the water that she has in the tank. It is one of the shapes you have a formula for.

Oh yeah I forgot about that thanks.
Is the answer yes?
because I worked out the cross sectional area using 1/2abSinC
then multiplied it by 50cm
= 9000cm^3
= 90 litres
so if one tablet is needed for every 15 litres
then only 6 tablets will be needed for 90 litres- right?
so she has enough but I have a feeling I went wrong somewhere :/

"Once a month"
In the working there is a missing 0 and no need to use sin area formula for a right angled triangle

I’m so confused
How are you meant to do it?
How would I work out the area without sin because isn’t it bxh/2 but I don’t know what the base is? And would the height be 50 cm?
Thank you

In the triangle, you're allowed to choose which sides are the base and perpendicular height, as long as they're perpendicular. You have a right angle so ...

Using the sin(C) rule is not wrong here, just unnecessary. What is sin(C) when you do it?

I thought sin c was 90 (so I got the area to be 1800cm2)
So is the area 60 x 50 /2 = 1500cm2

C is 90 so sin(C)=1. When you multiply by 1 the answer is unchanged.
So you're already doing base*height/2. 1800 is correct.

What year are you in?

"Once a month"
In the working there is a missing 0 and no need to use sin area formula for a right angled triangle

Where is the missing 0 🤔

C is 90 so sin(C)=1. When you multiply by 1 the answer is unchanged.
So you're already doing base*height/2. 1800 is correct.

What year are you in?

Just check your calcs. Shouldn't take more than a minute.

She goes through 6 tablets each month so that would mean 72 tablets in a year so she does have enough right?

I did and I still got the vol to be 90000cm3 ?

You posted nine thousand.

Do you really need to check that?