If the sum of the digits of a two-digit number is 9 and the number is 4 times the sum of its digits, what is the number? (2021)
Practice Questions
1 question
Q1
If the sum of the digits of a two-digit number is 9 and the number is 4 times the sum of its digits, what is the number? (2021)
36
45
54
63
Let the two-digit number be 10a + b, where a is the tens digit and b is the units digit. We have a + b = 9 and 10a + b = 4(a + b). Solving these gives a = 4 and b = 5, so the number is 45.
Questions & Step-by-step Solutions
1 item
Q
Q: If the sum of the digits of a two-digit number is 9 and the number is 4 times the sum of its digits, what is the number? (2021)
Solution: Let the two-digit number be 10a + b, where a is the tens digit and b is the units digit. We have a + b = 9 and 10a + b = 4(a + b). Solving these gives a = 4 and b = 5, so the number is 45.
