Answer:
234
Step-by-step explanation:
Let the digit in the hundreds place be a, the digit in the tens place be b and the digit in the ones place be c. So <u>a</u> <u>b</u> <u>c</u> is the number.
(Based on the question) a + b + c = 9 ----- Equation 1
<em>From Equation 1, you can get:</em>
<u>2a + </u><u>2b</u><u> + </u><u>2c</u><u> = 18 ----- Equation 2 </u>
<u />
(Based on the question) 2b = a + c ------ Equation 3
<u>(</u>Based on the question) <u>2a = c</u><u> ----- Equation 4 </u>
<em>Replace the c in Equation 3 with Equation 4: </em>
2b = a + 2a
<em>Evaluate. </em>
<u>2b = </u><u>3a</u><u> ----- Equation 5</u>
<em>Replace all the values of b and c with Equations 4 and 5 respectively into Equation 1 (Check underlined Equations to realise that all terms equal to a term in a): </em>
2a + 3a + 2(2a) = 18
<em>Evaluate. </em>
2a + 3a + 4a = 18
9a = 18
<em>Find a. </em>
a = 18 ÷ 9
a = 2
<em>Based on Equation 4, find c. </em>
c = 2 × 2
c = 4
<em>Based on Equation 1, find b. </em>
b = 9 - 2 - 4
b = 3
Piecing together the values of a, b and c, the number is 234.