#include <iostream>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <string>
#include <cstring>
using namespace std;
const int SIZE =
102;
const int INF =
0x3f3f3f3f;
int testcase;
int n;
int dp[SIZE];
int sum[SIZE];
int price[SIZE];
int add(
int i,
int j){
int res =
0;
for (
int k = i; k <=j ; ++k) {
res += sum[k];
}
return res;
}
int main(){
scanf(
"%d", &testcase);
while (testcase--){
memset(dp, INF,
sizeof(dp));
memset(sum,
0,
sizeof(sum));
memset(price,
0,
sizeof(price));
scanf(
"%d", &n);
for (
int i =
1; i <= n; ++i) {
scanf(
"%d %d", &sum[i], &price[i]);
}
dp[
0] =
0;
for (
int i =
1; i <= n; ++i) {
for (
int j =
1; j <=i ; ++j) {
dp[i] = min((add(j, i)+
10)*price[i]+dp[j-
1], dp[i]);
}
}
cout<<dp[n]<<endl;
}
}
