One canteen bought 129 kg of pork and mutton.
14 of the pork and
57 of the mutton were sold. The amount of mutton sold was 15 kg more than the amount of pork sold.
- How much mutton did the canteen buy?
- How much pork did the canteen buy?
|
Pork |
Mutton |
Total |
Before |
4x5 = 20 u |
7 u |
+ 21 |
129 |
Change |
- 1x5 = - 5 u |
- 5 u |
- 15 |
|
After |
3x5 = 15 u |
2 u |
+ 6 |
|
(a)
15 ÷ 5 x 7 = 21
15 ÷ 5 x 2 = 6
Total mass of pork and mutton bought
= 20 u + 7 u + 21
= 27 u + 21
27 u + 21 = 129
27 u = 129 - 21
27 u = 108
1 u = 108 ÷ 27 = 4
Mass of mutton bought
= 7 u + 21
= 7 x 4 + 21
= 28 + 21
= 49 kg
(b)
Mass of pork bought
= 20 u
= 20 x 4
= 80 kg
Answer(s): (a) 49 kg; (b) 80 kg