Page 172 - NUMINO Challenge_M1

EEExxxeeerrrccciiissseee 10- > 5, so 10- must be greater than 5, but less than 10.
10- can be 6, 7, 8, 9, or 10.
When 10- =6, =4.
When 10- =7, =3.
When 10- =8, =2.
When 10- =9, =1.
When 10- =10, =0.
5 numbers can go in , which are 4, 3, 2, 1, and 0.

Type Study John jump roped more than Ian, and the number of times Ian jump roped has a
larger ones digit, so the missing digit is 0.

Ian jump roped rope 204 times and Karen jumped 5 times. 204 >
5, so the hundreds digit for 5 is 1.

Karen jump roped more number of times than Alice so 1 5>186. The missing
tens digit it 9.

Problem solving

1 The number of acorns Gabe gathered is a 2-digit number. The number of acorns

Gabe gathered is the smallest.
The number of acorns Amy gathered has a 2 in the hundreds place, and is the
greatest.

Amy > Daniel > Gabe

2 Mary is older than Charles but younger than Jin, so she is 10 years old. Jin is older

than Mary but younger than Eunice, so he is 11.

Name Eunice Jin Mary Charles
Age 12 11 10 9

Type Study 10<20- <15. If 20- = , then 10< <15.
is greater than 10 but less than 15, so it is 11, 12, 13, and 14.

35Answer Key