Re: 11-plus grammar

the Omrud <usenet.omrud@xxxxxxxxxxxxxxxx> wrote
Arfur Million wrote:
"Leslie Danks" <leslie.danks@xxxxxx> wrote in message news:4868ab9c$0$2144$91cee783@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
If you try the test, Question 4 will tell you whether you belong to the
sheep or the rest:

<http://news.bbc.co.uk/today/hi/today/newsid_7478000/7478154.stm>
I didn't understand the scenario described (?) in question 2 at all - am I alone in this?

9 bricks in the first pile, 10 bricks in the second, etc. 7 piles, so the total number of bricks is 9 + 10 + 11 + 12 + 13 + 14 + 15.

As with many of this type of question, the total can be arrived at by the staggeringly useful formula for the area of a trapezium:

n/2(a + l)

where n is the number of steps, a is the first term and l is the final term:

7/2 (9 + 15)
3.5 x 24
84

I did it differently. There's a base rectangle seven bricks long and nine bricks high, so put 7 x 9 bricks down. Then there are 1, 2, 3, 4, 5 and 6 bricks on top, which are easily summed as 1+6, 2+5 and 3+4, which is three lots of seven. Total 12 lots of seven, or 84. It saves working with fractions until they are really needed, in some hypothetical later question.
--
Paul
.

Relevant Pages

  • Re: 11-plus grammar
    ... alone in this? ... bricks in the first pile, 10 bricks in the second, etc. 7 piles, so ... where n is the number of steps, a is the first term and l is the final term: ...
    (alt.usage.english)
  • Re: 11-plus grammar
    ... I didn't understand the scenario described in question 2 at all - am I alone in this? ... bricks in the first pile, 10 bricks in the second, etc. 7 piles, so ... where n is the number of steps, a is the first term and l is the final term: ...
    (alt.usage.english)
  • Re: 11-plus grammar
    ... bricks in the first pile, 10 bricks in the second, etc. 7 piles, so ... where n is the number of steps, a is the first term and l is the final ... What I did was imagine 7 piles of bricks with 9 bricks in the first pile ...
    (alt.usage.english)
  • Re: 11-plus grammar
    ... I alone in this? ... piles of bricks are placed side by side so that their tops form steps one ... If the lowest pile contains nine bricks, ... where n is the number of steps, a is the first term and l is the final ...
    (alt.usage.english)
  • Re: 11-plus grammar
    ... bricks in the first pile, 10 bricks in the second, etc. 7 piles, so ... If the lowest pile contains nine bricks, how many bricks are being used altogether?" ... My first stab at visualising the required scenario was to have the first pile as 3x3x1 (one brick high) and the next pile either as 3x3x2 or as any configuration that produced another step one brick high, but then I pretty well gave up. ...
    (alt.usage.english)