Page 141 - NUMINO Challenge_C1
P. 141
Answer Key
Number and Operations Problem solving
1 Clever Calculations p.8~p.9 1 The number of 4's and the number of 2's in the
Example 63, 6, 3, 6, 3 product will be the same as the number of digits
7, 2, 72, seven, 7777777622222223 in the numbers multiplied.
66666 and 66667 are 5-digit numbers.
66666 66667 4444422222
666666 and 666667 are 6-digit numbers.
666666 666667 444444222222
TryItAgain The product of 9 and 9 is 81, so 8 and 1 2 The even numbers become greater towards the
appear once. The number of 9's and the
number of 0's will be 1 less than the number center and become smaller afterwards. The
of 9's multiplied. Therefore, there are six 9's
and six 0's. greatest even number in the th line is 2.
9999999 9999999 99999980000001
Therefore, the sum of the number in each line is
( 2) .
The 9th line is 2 4 6 8 10 12 14 16
18 16 14 12 10 8 6 4 2, which is 18 9.
Example 2, 8, 5, 7, clockwise
8, 571428
Type 1-2 (A Number) (A Number Made Up of 9's) p.12~p.13
Type 1-1 Number Pyramids p.10~p.11
1 multiplicand-1
1 If the number of terms on the left side of the A multiplicand is the number to be multiplied.
equation is , the digit in the ones place is
10 . The digit of tens place is always 0. The 2 The sum of the first and second halves is equal to
digits in the hundreds and higher places are all the number made up of 9's in the multiplication.
1. The number of 1's is 1. 99, 999, 9999
2 Because the number of terms on the left side 3 The first half of the answer is
of the equation is 8, the digit in the ones place 82917325 1 82917324.
is 10 8 2. The digit in the tens place is 0, Therefore, the second half is
and there are 8 1 7 1's in the hundreds and 99999999 82917324 17082675.
higher places altogether. 111111102 8291732417082675
Because the number of terms on the left side
of the equation is 9, the digit in the ones place
is 10 9 1. The digit in the tens place is 0,
and there are 9 1 8 1's in the hundreds and
higher. 1111111101
3 The value of the greatest digit is equal to the
number of 1's in the number multiplied.
12345678987654321
NUMINO Challenge C1
Number and Operations Problem solving
1 Clever Calculations p.8~p.9 1 The number of 4's and the number of 2's in the
Example 63, 6, 3, 6, 3 product will be the same as the number of digits
7, 2, 72, seven, 7777777622222223 in the numbers multiplied.
66666 and 66667 are 5-digit numbers.
66666 66667 4444422222
666666 and 666667 are 6-digit numbers.
666666 666667 444444222222
TryItAgain The product of 9 and 9 is 81, so 8 and 1 2 The even numbers become greater towards the
appear once. The number of 9's and the
number of 0's will be 1 less than the number center and become smaller afterwards. The
of 9's multiplied. Therefore, there are six 9's
and six 0's. greatest even number in the th line is 2.
9999999 9999999 99999980000001
Therefore, the sum of the number in each line is
( 2) .
The 9th line is 2 4 6 8 10 12 14 16
18 16 14 12 10 8 6 4 2, which is 18 9.
Example 2, 8, 5, 7, clockwise
8, 571428
Type 1-2 (A Number) (A Number Made Up of 9's) p.12~p.13
Type 1-1 Number Pyramids p.10~p.11
1 multiplicand-1
1 If the number of terms on the left side of the A multiplicand is the number to be multiplied.
equation is , the digit in the ones place is
10 . The digit of tens place is always 0. The 2 The sum of the first and second halves is equal to
digits in the hundreds and higher places are all the number made up of 9's in the multiplication.
1. The number of 1's is 1. 99, 999, 9999
2 Because the number of terms on the left side 3 The first half of the answer is
of the equation is 8, the digit in the ones place 82917325 1 82917324.
is 10 8 2. The digit in the tens place is 0, Therefore, the second half is
and there are 8 1 7 1's in the hundreds and 99999999 82917324 17082675.
higher places altogether. 111111102 8291732417082675
Because the number of terms on the left side
of the equation is 9, the digit in the ones place
is 10 9 1. The digit in the tens place is 0,
and there are 9 1 8 1's in the hundreds and
higher. 1111111101
3 The value of the greatest digit is equal to the
number of 1's in the number multiplied.
12345678987654321
NUMINO Challenge C1
