It's total unchanged. So the total units is 10 units.

Thank u.. see the 2nd picture n understand everything ...

Is this one of the questions for 21 to 23? We can't really tell how many flat surfaces there are because the view from the right side is not shown and there are a few possibilities of what it could be on the side...

Yes and my question is 23.

Then, assuming that the solid is made up of a cuboid and the L-shaped part at the end, there will be 6 sides from the cuboid + 4 from the L block to make it a total of 10.

Ok thanks

We think model answer is wrong so we check here.

What was answer given?

11

Should be 10 😊

Ok thanks then wrong answer I suppose

My gf gave this reasoning for 11 Than the small cube that face inward Not sure can that face be compute same face with the 3cube beside it

Should be counted as one face otherwise the outside face would be counted twice, making it 12 or even 13...

This question is so confusing!

Think must write to publisher!

This question is not well defined as there may be cubes hidden behind. We need to assume that no cubes are hidden. Viewing from the top, there are 2 faces; from the right, 3 faces; from the back, 2 faces. There is 1 face each from the left, from the front, and from the bottom. Altogether there are 10 faces.

Alright! Thanks

Someone has solved Question 13 before and the answer is 98.

Q14. Use branching.

Here's the recommended solution.

Solution is correct, however you have given the number of Vans that left not remained. Here is an alternative solution. If you break the question down, there is two parts. One using the words Remainder to find the "Starting" ratio of the vehicles. Then using the change we can compare the before and after ratios.

Yup.. My bad.. Actually found the number of vans left parked at the carpark when I worked out 20%.. 60

I can't draw a diagram now but essentially x (weight of Mark) + (x+4) = 124. Thus 2x = 124 - 4. x = 120/2. My son will draw a diagram and use a box in place of x to rep M's weight and a longer box to rep B's weight. The longer box will be shorter box plus 4 kg.

Solution 1 can be 124 ÷ 2= 62 (assuming both have equal mass). Then 62-2 =60. Coz the difference between bala and mark is 2+2=4.

Mark weighs 60kg. Solution 2.

Just a suggestion please. Notice that if you assume Solution 1 is correct, then by checking back: Mark's mass = 58 and Bala's is 62. But 58 + 62 = 120. This already disagrees with the original given value in the question so cannot be a correct method.

The reasoning for Solution 1 is incorrect because subtracting 4 from 62 (obtained by assuming that both masses are equal) is already ascertaining that Bala's mass is 62kg.

Thank you all for the speedy respond and help!

subtract to get equal weight before dividing by 2. Then add the 4kg back to the single weight to get the weight differences.