More solutions for problem one
Thought of five and eight-tenths as 5.8, ignored the decimal and thought of multiples of five
5 *
10 = |
50 |
5 *
11 = |
55 |
5 *
12 = |
60 |
from this information could go three ways:
1. Think that a fifth of 55 is 11 and a fifth of 3 (55 + 3 = 58) is 3/5 or 6/10. Together they are 11 and 6/10 or 11.6. But the 11 is ten more than one and one tenth so the answer needs to be divided by ten and you get 1.16
2. The same can be done only you could work backwards from 12 and 60. A fifth of 60 is 12 and a fifth of 2 (60 - 2 = 58) is 2/5 or 4/10. Together it would be 12 - .4. But 12 is ten more than one and two tenths so the answer needs to be divided by ten and you get 1.2 - .04 or 1.16
3. Make the same chart and add places for numbers between 55 and 60. The values between 11 and 12 increase incrementally and the only value that could work would be .2. So the value with 58 would be 11.6. However, that value needs to be divided by one tenth.
5 *
10 = |
50 |
5 *
11 = |
55 |
5 *
11.? = |
56 |
5 *
11.? = |
57 |
5 *
11.? = |
58 |
5 *
11.? = |
59 |
5 *
12 = |
60 |
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