Page 143 - NUMINO Challenge_M2

Answer
Key

3. Operation Symbol
EEExxxeeerrrccciiissseee The number in the middle of the triangle is the number at the top corner

subtracted from the sum of the two bottom numbers.
The missing number is 3+1-2=2.

Type Study The following shows the sum, difference, and product of each set of silver
and copper coins.

Sum Difference Product Gold coins

A (1, 2) 1+2=3 2-1=1 1^2=2 2

B (2, 1) 2+1=3 2-1=1 2^1=2 2

C (1, 3) 1+3=4 3-1=2 1^3=3 3

D (3, 0) 3+0=3 3-0=3 3^0=0 4

Among the sum, difference, and product of silver and copper coins, the
difference is always one less than the number of gold coins.

Since the difference between the number of silver coins and copper coins
is always one less than the number of gold coins, (gold coins)=(difference
between silver and copper coins)+1. So, when 3 silver coins and 3 copper
coins are put into the magic purse.

The number of gold coins that are made is 3-3+1=1.

Problem solving

1 Rules for using the given symbol, , can be found by looking at the given

examples. The number to the right of goes in the tens place of the number

that follows the equals sign. The number to the left of goes in the ones place

of the number that follows the equals sign. If the number to the right of the

symbol is 0, the resulting number is a 1-digit number.

8 1=18 4 0 =4

2 The top number multiplied by 2 equals the sum of the two numbers at the

bottom of the triangle. If the missing number is , then 5^2= +6.
Therefore, =4.

6 NUMINO Challenge M2