Muffins are sold in Kathy Cake Shop at the prices as shown:
1 chocolate chip muffin $2.40
1 apricot muffin $1.80
MrsChong bought 7 more apricot muffins than chocolate chip muffins from this cake shop. She paid $21 in total. How many muffins did Mrs Chong buy altogether?
|
Chocolate chip muffins |
Apricot muffins |
Total muffins |
Number |
1 u |
1 u + 7 |
|
Value |
2.40 |
1.80 |
|
Total value |
2.4 u |
1.8 u + 12.6 |
4.2 u + 12.6 |
Amount that Mrs Chong paid for chocolate chip muffins
= 1 u x 2.40
= 2.4 u
Amount that Mrs Chong paid for apricot muffins
= 1.80 x (1 u + 7)
= 1.8 u + 12.6
Total amount that Mrs Chong paid
= 2.4 u + 1.8 u + 12.6
= 4.2 u + 12.6
4.2 u + 12.6= 21
4.2 u = 21 - 12.6
4.2 u = 8.4
1 u = 8.4 ÷ 4.2 = 2
Number of muffins that Mrs Chong bought altogether
= 2 u + 7
= 2 x 2 + 7
= 4 + 7
= 11
Answer(s): 11