Q&A - P5 Math

[ttlkbs]

Another question on area, pls help :

[ttlkbs]

3rd and last question on area for this holiday!
Help pls :

[AdaptiveLearning.sg]

Another question on area, pls help :

Height of small triangle
= 1/2 x height of square (since P is the mid point)
= 1/2 x 15

Area of small triangle
= 1/2 x base x height obtained above
= 1/2 x 15 x 7.5

Area of bigger triangle
= 1/2 x base x height of square
= 1/2 x 15 x 15

Shaded Area
= Area of bigger triangle - Area of smaller triangle

[AdaptiveLearning.sg]

3rd and last question on area for this holiday!
Help pls :

Not sure if my calculations are off, but I can't get a consistent answer for this one.

Assuming the mid-point of BC is P.

The shortest calculation should be:
(i)
Area of triangle KEL
= Area of Rectangle formed by points K, P, E
= Area of ABCD / BP x KP
= 94 / 3 x 2.5

(ii)
However, using the similar triangles...
Area of triangle KEP
= Area of triangle KGB x (KP/KB)^2
= 6 x (2.5/1)^2
Area of triangle KEL
= 2 x Area above

The two yield different answers.

[ttlkbs]

Another question on area, pls help :

Height of small triangle
= 1/2 x height of square (since P is the mid point)
= 1/2 x 15

Area of small triangle
= 1/2 x base x height obtained above
= 1/2 x 15 x 7.5

Area of bigger triangle
= 1/2 x base x height of square
= 1/2 x 15 x 15

Shaded Area
= Area of bigger triangle - Area of smaller triangle

It's so simple! Why couldn't I think of it?

[ttlkbs]

3rd and last question on area for this holiday!
Help pls :

Not sure if my calculations are off, but I can't get a consistent answer for this one.

Assuming the mid-point of BC is P.

The shortest calculation should be:
(i)
Area of triangle KEL
= Area of Rectangle formed by points K, P, E
= Area of ABCD / BP x KP
= 94 / 3 x 2.5

(ii)
However, using the similar triangles...
Area of triangle KEP
= Area of triangle KGB x (KP/KB)^2
= 6 x (2.5/1)^2
Area of triangle KEL
= 2 x Area above

The two yield different answers.

77

Maths Tutor Mr Lim, would you like to share how did you derive at 77 ?

[MathIzzzFun]

3rd and last question on area for this holiday!
Help pls :

Not sure if my calculations are off, but I can't get a consistent answer for this one.

Assuming the mid-point of BC is P.

The shortest calculation should be:
(i)
Area of triangle KEL
= Area of Rectangle formed by points K, P, E
= Area of ABCD / BP x KP
= 94 / 3 x 2.5

(ii)
However, using the similar triangles...
Area of triangle KEP
= Area of triangle KGB x (KP/KB)^2
= 6 x (2.5/1)^2
Area of triangle KEL
= 2 x Area above

The two yield different answers.

DIscussed @pg 335 --> http://tinyurl.com/ksp-P5maths-pg335

cheers.

[belnanna]

Please help anyone? Thanks in advance
A store sells pens in packs of 2s (small) and 4s (big).
At first there were 3 times more small packs than big packs.
After selling half of the small packs and some big packs, the shopkeeper packs
additional 5 big packs of pens. How many big packs are sold if there are thrice as many small packs as big packs and there is total 300 unsold pens?

[ttlkbs]

3rd and last question on area for this holiday!
Help pls :

Not sure if my calculations are off, but I can't get a consistent answer for this one.

Assuming the mid-point of BC is P.

The shortest calculation should be:
(i)
Area of triangle KEL
= Area of Rectangle formed by points K, P, E
= Area of ABCD / BP x KP
= 94 / 3 x 2.5

(ii)
However, using the similar triangles...
Area of triangle KEP
= Area of triangle KGB x (KP/KB)^2
= 6 x (2.5/1)^2
Area of triangle KEL
= 2 x Area above

The two yield different answers.

DIscussed @pg 335 --> http://tinyurl.com/ksp-P5maths-pg335

cheers.

Thanks to all who have offered solutions.

[geniuskids]

Need help on this question:

Islani had to read a book for his school project. On the 1st day, he read 72 pages of the book. On the 2nd day, he read 1/4 of the remaining number of pages. In the end, he still had to read 1/2 of the total number of pages to complete the book. How many pages were there in the book?

Thank you.